Cases 4. Cases. Determining the case of a noun

Declension of nouns is the change of nouns in cases.

declination- a set of changeable forms (inflections) of names (nouns, adjectives, numerals, pronouns) according to numbers, genders and cases.

The type of declension (or simply declension) is the category of the name - a certain grammatical type of variability, such that words of the same type of declension have the same or similar forms of change.

Declension forms are determined by both the semantic role and the form of the governing member of the sentence. The semantic role can control case and number, and then declension is a semantic element of the language. For example: the cat is walking - the word cat is in the nominative case, singular and means that one cat performs an action; cats are walking - already plural, which means there are several cats; the cat is fed - the cat is in the accusative case, therefore the action is performed on the cat.

Declension (tracing paper from Latin declinatio, “deviation” from the main form of the word) is the inflection of nominal parts of speech (nouns, adjectives, pronouns, numerals). Usually, the term "declension" means inflection according to the grammatical categories of number and case.

The word "declension" is also used in the sense of "a certain type of paradigm of declension". They talk about the types of declension of individual parts of speech (for example, in Russian they distinguish substantive - declension of nouns, adjective - declension of adjectives and pronominal declension) and individual groups of words within one part of speech. So, traditionally in the Russian substantive declension, I (head - heads), II (table - tables) and III (notebook - notebooks) types of declension are distinguished, as well as special cases: indeclinable words (in which all forms coincide in both numbers: metro, kangaroo, beige, etc.) a few words with -en- in indirect cases (time - time), two words with -er- in indirect cases (mother - mother, daughter - daughter), a special declension Christ - Christ, etc. Other, more economical ways of classifying Russian inflectional paradigms were also proposed, for example, A. A. Zaliznyak combines traditional I and II declensions into “I substantive declension type” with endings that differ depending on the morphological gender.

1st declension- all feminine and masculine words ending in -а or -я (book, mom, dad, biology, physics, mathematics, computer science).
For nouns of the first declension of the singular in the dative and prepositional cases, the ending -e is written, for example: to dad, about the book. But if the noun ends in -iya, then in the same cases the ending -i is written, for example: to chemistry, about biology. When writing the endings of proper names in -iya, you must adhere to the same rule, for example: to Xenia, about Italy:

2nd declension- all other masculine and neuter words (poppy, stump, bug, slope, biofield, glass).
In the second declension of nouns, the form of the accusative case in most cases coincides with the form of the nominative case (glass, biofield) or the genitive case (slope, stump).
For singular nouns of the 2nd declension, masculine or neuter, the ending -e is written in the prepositional case, for example: about the biofield, about the glass. But if the noun ends in -й or -е, then in the same case the ending -i is written, for example: about consciousness, about trust, about difference:

3rd declension- all other words are feminine (night, fabric).
In the third declension, in most cases, the forms of the genitive, dative and prepositional cases of the singular coincide.
After hissing at feminine nouns of the third declension, “b” is written at the end, for example: silence, daughter. And for masculine nouns of the second declension, “b” is not written, for example: rage, kalach, baby.

Publication date: 06/09/2011 09:31 UTC

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In addition to the three types of declension of nouns accepted for study, there are several more categories in the grammar of the Russian language. The modification of a word according to number, gender and case is denoted by the term "declension". This transformation forms new parts of the word or changes their original form. Only nominal parts of speech are subject to declension.

The belonging of a part of speech to certain types of declension is revealed by their inherent endings, the word must be in its original form (nominative case, singular).

First declension of nouns

The indicated parts of speech, which are in the masculine or feminine gender, are related to the first type of noun declension, whose initial form (nominative case) differs by the endings -а or -я.

Examples: ruler- A (female) , birch- A (female) , plate- A (female) , magnoli- I (female) , grandfather- A (m.s.) , dad- A (m.s.) , planets- A (female) , category- I (female) .

It should also be borne in mind that this declension also includes nouns of the general gender (words whose gender is determined by the semantic load or context in which they are used).

Examples: confused- A, roar- A, confused- A, quiet- I, orphans- A, dirty- I .

Depending on the word with which they are used, their gender changes: Confused Polina (female) — Confused Dima (m.). Tikhonya girl (female) - Tikhonya boy (m.b.).

Second declension of nouns

Masculine words ending in -o or -e also belong to the second declension: house- O, voice- e, man- O.

Neutral nouns that end in -o or -e are also parts of speech of the second declension: mountains e, lakes- O, towels e, farewell- e, craft- O, knee- O, decrease- e.

Third declension of nouns

Examples: midnight b_, daughter b_, bed b_, help b_, area b_, youth b_, love b_, mouse b_.

Three declensions of nouns (table)

Inflected nouns

In particular cases, the rules for declension of nouns are violated. These words must be remembered:

• neuter nouns ending in -me, there are 10 in total: flame, time, burden, banner, and-me, tribe, you-me, stirrup, se-me, those;
• child(cf. gender);
• path ( m. genus).

These words acquired such a name due to the correspondence of their endings in the instrumental case to the endings of the second declension, but otherwise they have all the features of nouns of the 3rd declension. An example of the formation of new endings when converting by case forms:

• Nominative: path_; striving I; dit- I; youth_.
• Genitive: put- And; stirrup- And; child- And; youth And.
• Dative: put- And; stirrup- And; child- And; youth And.
• Accusative: path_; striving I; dit- I; youth_.
• Instrumental: put- eat; stirrup- eat; child- to her; youth- Yu.
• Prepositional: oh put- And; about stirrups And; oh baby- And; about youth And.

Nouns formed from other parts of speech and retaining their features are distinguished into a special group. These words include nouns with signs of adjectives, numerals and participles (worker, day off, subject, animal, worker, tailor, shower, second, subtracted). Declension, which includes such parts of speech, is called adjective. According to him, these nouns will decline, as well as the part of speech, the features of which it possesses.

Nouns that cannot be used in the singular make it difficult to determine the gender, so they do not have it, as well as declensions: glasses, bran, yeast, holidays, spirits, Carpathians, fees, chess, swings, shadows, cream.

Indeclinable nouns also include words borrowed from other languages ​​that do not change their ending in any of the cases: maestro, entertainer, kiwi, flamingo, cockatoo, lady, salami, kohlrabi, aloe.

Determining the declension of a noun

Video

From the history.

After the adoption of Christianity in Rus', there was a need to teach people to read and write. To do this, it was necessary to normalize or systematize the language. Grammar did not yet exist at that time.

At the beginning of the XIV century, from various Greek grammatical treatises, an essay "On the eight parts of the word" (that is, "speech") was compiled in Serbia. In accordance with the Greek system, five cases are defined for the Slavic language. Their names, as well as the word "case" (or "fall") itself, were formed by tracing (translating the word in parts) of the corresponding Greek terms.

Word " case"(Greek ptosis) denoted a change in ending, due to which the word becomes in a certain relationship to other words. In the essay "On the Eight Parts of the Word" these relations are presented as follows.

Right case(Laternominative) calques from the Greek orte and gives the correct or original form of the word. The philologist of the late 16th century, Maxim the Greek, called this case direct. All other cases are indirect in relation to it (or oblique, Greek plagiai), since they decline, that is, deviate from it. The modern term declension appeared in the 16th century, representing a tracing paper from the Latin declinatio.

Second case - native (Greek genike), one of the functions of which is the designation of the genus, origin, assignment of an object to a class of similar ones (a work of art).

Dative (Greek dotike) is named after one of its functions associated with the verb to give, to give.

Guilty case(Greek aitiatike) - derived from the word "guilt" (Greek aitia), which in ancient times had the meaning "reason", and is considered as a case of designating the cause of an action (to catch a butterfly).

Fifth case - vocative (Greek kletike), which was used when addressing. In modern Russian, traces of it remained in the form of forms: father, elder, friend, and its functions are performed by the nominative case. True, now a new vocative case is being formed (Vas, Sing, Light).

But the Greek system did not meet the needs of studying the Slavic languages, since it did not have Instrumental and Prepositional cases.

At the beginning of the 16th century, the embassy translator Dmitry Gerasimov translated Donatus, a treatise on Latin grammar of the 4th century, popular in Europe. This is where the term first appears. nominative fall , with the explanation "right in Greek", which was a tracing paper from the Latin Nominativus. The remaining cases have the same names, since the Latin terms were calques from ancient Greek.

The main difference of the Latin system, however, was that it contained Ablativus. Dmitry Gerasimov named it Negative Fall and provided an example "from this teacher". The given meaning, now called the deposition, does not exhaust the functions of this case: it corresponds to our Instrumental case with another meaning.

Soon, in the Grammar of Lawrence Zizania (1596), a designation of similar Slavic forms appears - Instrumental case (The word "fall" by that time had fallen out of use). The function of the highlighted case was to indicate the actor, the producer of the action. Forms Prepositional he highlights under the rubric Dative case.
The grammar of Meletius Smotrytsky, published in 1619, introduced the seventh case - Descriptive, the name of the case was derived from such cases of its use as "to say about someone, about something."
M. V. Lomonosov in "Russian Grammar" replaces Descriptive to Prepositional, drawing attention to the fact that the forms of this case are used exclusively with prepositions. It was the first grammar dealing with the Russian language, all the previous ones dealt with the Church Slavonic language. But Lomonosov did not rule out vocative case, to which by that time was already of little use. It was eliminated in later grammar works. http://answer.mail.ru/question/13431713

Additionally

TO how to distinguish
Genitive
from Vinitelnog O.

Instruction

1 Determine whether the analyzed noun is animate or inanimate. An animate noun in the genitive and accusative case answers the key question "whom?". An inanimate noun answers the question “what?” in the genitive case, and the question “what?” in the accusative case, which coincides with the interrogative word for the nominative case.

2 Check the noun for compatibility with certain words. In the genitive case, the noun is combined with the word "no". For example, "No what?" - "Chair" or "There is no one?" - "Student". It is customary to check the accusative case by compatibility with verbs in the first person, singular and present tense: “I see”, “I know”, “I love”. For example, "See what?" - "Chair" or "I see who?" - "Student". In this example, you can see that the accusative and genitive forms of animate masculine nouns of the II declension coincide.

3 Replace an animated masculine noun of the II declension with any word of the I declension. For example, "No one?" - "Students" or "I see whom?" - "Student". In the I declension, it is easy to determine the ending -ы for the genitive and -у for the accusative case.

Great and rich, so many subtleties in it that it seems impossible to remember everything. In fact, there is nothing complicated. Just for each question you need to be able to find the right solution. Let's look together at how many cases there are in Russian, what questions they answer, and the easiest way to remember them.

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Definition

What is a fall? To begin with, it is worth familiarizing yourself with the concept itself. . Case is a form that indicates relationship between words. With its help, the proposal can be agreed and formed. Eg:

1. We, joy, accept, he, the team.
2. We gladly accepted him into the team.

In the first variant, there is simply a set of words that are in no way related to each other. In the second paragraph, thanks to the shape change, we get a complete sentence with a formed thought.

How many cases are there in Russian? The common number is six. That is how much is offered for the study of students. However, linguists argue that the present number 15. Apparently, in order to simplify the system, it was decided to remove some of them from the curriculum.

Main types

All nouns are comparable to questions and auxiliary expressions. Their interaction with each other is very convenient: if you forget one thing, another can come to the rescue.

Some cases questions match, and to distinguish between them, you can turn to declensions for help.

What are the main cases in Russian.

Nominative

Used to name objects, has the following identifying features:

• questions who? - Mother. What? - frame;
• auxiliary expression "is";
• occurs with endings in the singular: I skl: -a, -ya. II: -oh, -e. III:ÿ;
• plural: -s, -i, -a, -i.

1. Marina has always loved to read books. Is there anyone? - Marina (1 class).
2. The leaves fluttered in the wind. Is there anything? - Leaves (1 cl.).

Genitive

Defines an ownership. To facilitate the memorization of the genitive case in Russian, there are a number of ways:

• you can compare it with the expression "no" who? - father. What? Palace;
• used with prepositions: at, around, before, with, from, near, without, from, after, about, for;
• ending in singular: I skl: -s, -i. II: -a, -z. III: -and;
• in the plural: -ov, -ev, -ey.

1. After my mother left, we were a little upset. No one? - Moms (1st class).
2. There were no horses in the stable. There is nothing? - Horses (plural).

Dative

It has a hint in the name itself, to pass something to someone. Its features:

• defines the last action point;
• "give" to whom? - a boy. What? - a glass;
• prepositions: by, to;
• endings in unit number: I skl: -e, -i. II: -y, -y. III: -and;
• in the plural: -am, -yam.

1. Grandma didn't like our game. Give to whom? - Grandmother (1st class).
2. Running across the field was a lot of fun. Give what? - Field (2 cl.).

Accusative

Names the action object:

• "I see" who? - girlfriend. What? - hand;
• prepositions of the accusative case: through, on, in, for, about;
• endings in unit number: I skl: -y, -y. II: -o, -e;
• in the plural: -, -s, -and, -a, -ya, -her.

1. It was especially nice to hear from the little sister. I see who? - Sister (1st class).
2. A dog was running across the bridge. See what? – Bridge (3rd declension.).

Instrumental

The belonging of a part of speech to this case is determined as follows:

• "admire" who? - wife. How? - chain mail;
• used with prepositions: over, before, under, with, for;
• endings in the singular: I declension: -oy, -oy, -ey, -ey. II: -om, -em. III: -e: -yu;
• in the plural: -ami, -ami.

1. Before which stop did you ask to stop? Love what? – Stop (1st line).
2. Lena and I have been friends since the fifth grade. I love who? - Lena (1 cl.).

Prepositional

Always used with prepositions, and also has the following properties:

• most often used prepositions - on, with, about, in, about;
• "I dream" about whom? - about a fox. About what? – about the assessment;
• endings in unit number: I skl: -e, -i. II: -e, -i. III: -i.
• plural: -ah, -ya.

1. My dream of having a puppy has finally come true. Thinking about who? - Puppy (1 declension.).
2. A birch grove grew at the court. Think about what? - Yard (1 declension.).

To memorize all the names, children can be asked to learn a short sentence:

• Irina
• gave birth
• girl
• Velela
• drag
• diaper.

Table - cases.

Additional varieties of case forms

1. Vocative. It could include appeals to someone created by "circumcision". Example: mom, dad, Tan, etc.
2. Local. Prepositions: at, at, on. Answers the questions: where, on what? Example: on the bedside table, at the school yard.
3. Dividing. Genitive derivative In russian language. Example: add speed, set the heat.
4. Countable. Used with numbers. Example: four balls, two cabinets.
5. Deferral. Indicates starting point of movement. Example: from the garden, from the house.
6. Depriving. To negate verbs. Example: Can't go, not ready to say goodbye.
7. Quantitative-determinative. It has similar traits to the parent. Example: a cup of tea.
8. Waiting. Example: wait for a friend.
9. Transformative (inclusive). Example: go to the sailors, go to the stewardesses.

Noun declension

Every noun can be inflected. There are 1, 2 and 3 declensions, as well as words related to this part of speech, may be divergent. These include the words "way", "ten", and nouns ending in "me".

Declension of nouns, table.

case	I declension		II declension		III declension
	Female genus	Husband. genus	Husband. genus	Wed genus	Female genus
Nominative	Road A	pap A Coast I	Watermelon	Zhit O Mor e	Salt
Genitive	Road And	pap s Coast And	Watermelon A Korn I	Zhit A Mor I	Sol And Gran And
Dative	Road e	pap e Coast e	Watermelon at Korn Yu	Zhit at Mor Yu	Sol And Gran And
Accusative	Road at	pap at Coast Yu	Watermelon	Zhit O Mor e	Salt
Instrumental	Road Ouch An to her	pap Ouch Coast to her	Watermelon ohm Korn eat	Zhit ohm Mor eat	Salt Yu edge Yu
Prepositional	Oh dear e About An e	Oh dad e Oh Coast e	About watermelon e Oh corn e	Oh life e Oh mor e	Oh sol And Oh gran And

Attention! Only the nominative case is considered direct, the rest are indirect.

Cases and questions

Case and auxiliary word			Prepositions	Endings by numbers
				Unit h.
						III fold.
Nominative	Who? (father). What? (telephone)	My father always read a lot. The phone rang several times a day.	Without pretexts	-and I	-, -o, -e	—	-s, -i, -a, -i
Genitive	Whom? (parents). What? (inspiration)	There were no parents in the kitchen. I had to draw without inspiration.	Around, at, before, with, from, near, for, from, without, about, after	-s, -and	-and I	-And	-ov, -, ev, -ey
Dative	To whom? (to a kitten). What? (ceiling)	Masha poured milk for the kitten. Garlands were attached to the ceiling.	By, to	-e, -and	-u, -u	-And	-am, -yam
Accusative	Whom? (friend). What? (house)	We invited a friend along. Moving to a new house was not fun.	Through, for, in, on, about	-u, -u	-o, -e	—	-, -i, -s, -a, -i
Instrumental (admire)	By whom? (artist). How? (creation)	She always dreamed of becoming an artist. Katya has been admiring her creation for the fifth hour already.	Under, behind, before, with, over	-oh / oh, -ee / her	-om, -em	-Yu	-ami, -ami
Prepositional	About whom? (about Masha) About what? (about travel)	We didn't even think about Masha. Mom has been thinking about this trip for a long time.	Oh, in, oh, at, on	-e, -and	-e, -and	-And	-ah, -i

How to learn cases easily

How to easily and simply determine the case of a noun and an adjective

Conclusion

For faster and easier memorization, you just need to choose a more convenient option - visual materials. For example, for visual perception easier to work with tables and charts. So cases and questions will not cause you any problems.

1. Nouns belong to one of the three childbirth: male, female, average.

The gender of a noun can be determined by agreeing with it the possessive pronoun mine:

my son, my governor, my curtain, my house - masculine;
my wife, my wall, my night - feminine,
my window, my sky, my animal - neuter gender.

In addition, for most nouns denoting people, gender can be determined by gender - my apprentice, my grandfather(masculine); my mother, my sister(feminine gender).

2. Genus immutable nouns is defined as follows.

The gender of immutable nouns that name people is determined by gender.

Brave hidalgo, exquisite lady.

Nouns denoting professions and occupations are masculine.

Military attache, night porter.

Invariable nouns naming animals are masculine, although when referring to a female they can be used as feminine nouns.

Australian kangaroo, funny chimpanzee, little hummingbird.
The chimpanzee nursed her young.

Exceptions: tsetse, iwashi- feminine gender.

Immutable inanimate nouns are neuter.

Night taxi, tasty stew, new blinds.

Exceptions: coffee, penalty, sirocco(masculine) avenue, salami(feminine gender).

3. Nouns are a special group generic, which can represent both male and female people.

What a slut you are! What a slob you are!

General nouns characterize a person, usually give an evaluative characteristic to a person, have the endings -а, -я and belong to the 1st declension.

A slob, a ringleader, a singer, a hard worker, a dirty man, a dude, a drunkard, a sissy, a sleepyhead, a crybaby.

Note!

Some nouns of the 2nd declension with a zero ending, naming persons by profession ( doctor, professor, associate professor, driver etc.), although they can be used in relation to females, they are still masculine nouns!

4. The gender of nouns is determined by the singular form. If a noun does not have a singular form, it cannot be assigned to any of the three genders.

Manger, pasta, trousers, pitchfork.

B) The number of the noun

1. Most nouns have two numbers - the only thing And plural. In the singular form, the noun denotes one object, in the plural form, several objects.

Pencil - pencils; doctor - doctors.

2. Only one form(singular or plural) have real, collective, abstract and some specific nouns.

Only form singular have:

most real nouns;

Oil, cement, sugar, pearls, sour cream, milk.

most abstract nouns;

Joy, kindness, grief, fun, redness, running, gray hair.

most collective nouns;

Teaching, students, foliage, animals, crows, children.

most proper names.

Voronezh, Caucasus, Caspian, Ural.

Note!

In some cases, nouns that have only the singular form can form plural forms. But such an education is necessarily associated with a change in the meaning of the word:

1) at material

a) types, varieties of substances:

wine - dessert wines, oil - industrial oils;

b) the value of the large area covered by this substance:

water - the waters of the ocean, sand - the sands of the Karakum;

2) at abstract nouns plural form has meaning:

a) various manifestations of qualities, properties, states:

opportunity - new opportunities, joy - our joys;

b) duration, repetition and degree of manifestation of a sign, state, action:

frost - long frosts, pain - severe pain, cry - screams.

Only form plural have:

some real nouns;

Ink, sawdust, cleaning.

some abstract nouns;

Name days, elections, attacks, intrigues, beatings.

• some collective nouns;

  Money, finance, wilds.

some proper names;

Karakum, Carpathians, the novel "Demons".

words denoting paired objects, that is, objects consisting of two parts;

Glasses, trousers, sleds, gates, scissors, tongs.

some names of time intervals.

Twilight, day, weekdays, holidays.

Note!

For nouns that have only a plural form, not only the gender is not determined, but also the declension!

C) Case and declension of nouns

1. There are six in Russian cases:

All cases except the nominative are called indirect.

Note!

1) To correctly determine the case of a noun, you need to find the word on which the noun depends, and ask a question from this word to the noun, and it is better to use both questions at the same time.

Wed: He believed a friend: believed[to whom? what?] friend - D. p.

The subject usually has the form I. p., and such a noun does not depend on other members of the sentence, but is connected with the predicate.

Wed: I have[Who? what?] friend - I. p.

2) It is especially important to ask both questions if the noun is in the nominative, genitive, or accusative case, since animate nouns have the same genitive and accusative questions (who?), while inanimate nouns have the same nominative and accusative questions (what?).

3) If the noun has a preposition, then the question must be asked using that preposition.

Wed: He looked into the book: he looked[in whom? into what?] in a book.

4) A preposition can be separated from a noun by an adjective, a pronoun. Note that the preposition is noun-related, not noun-dependent.

Wed: He quarreled with his friend: quarreled[with whom? with what?] with a friend.

2. Changing nouns in cases and numbers is called declension.

Invariable nouns ( coat, sitro, subway, taxi, kangaroo, UN, traffic police) have no declension! Their number and case can be determined in phrases and sentences on the issue.

He was sitting[in whom? in what?] V coat - singular, prepositional; He came[without whom? without which?] without coat - singular, genitive.

3. The declension of inflected nouns is determined by the form nominative singular. Most singular nouns fall into three types of declension.

The type of declension is determined by the initial form (singular, nominative):

1st fold.	-and I	Feminine, masculine and common nouns with endings -а, -я.	Spring, earth, line, uncle, lord, dirty.
2nd fold.	zero	Masculine nouns with a null ending.	House□ , edge□ , ball□ , planetarium□ .
	-o, -e	All nouns ending in -o, -e.	Window, field, suspicion- neuter gender; wolf, apprentice- masculine.
3rd fold.	zero	Null-ending feminine nouns.	Mother□ , daughter□ , night□ , steppe□ .

4. Ten neuter nouns ending in -my (ending -я): time, burden, stirrup, tribe, flame, banner, crown, seed, name, udder, as well as nouns way, child refer to heterogeneous(they have endings of different declensions).

5. The noun man has different roots in singular and plural ( person people), therefore it has different types of declension in singular and plural:

person (singular) - declined as a noun of the 2nd declension;
people (plural) - inflected as a noun of the 3rd declension.

6. Substantive adjectives and participles (nouns formed by transition from one part of speech to another: ice cream, dining room, living room, maid etc.) do not belong to any of the three types of declension. They continue to inflect the way adjectives and participles inflect!

D) Noun declension patterns

1st declension

case	Singular			Plural
I. p.	Mother	Nanny	Aria	mothers	Babysitters	Arias
R. p.	mothers	Babysitters	Arias	Mom	Nian	Arius
D. p.	Mom	babysitter	Arias	Mom	Babysitting	Ariyam
V. p.	Mom	babysitter	Aria	Mom	Nian	Arias
T. p.	Mom(s)	Babysitter(s)	Aria(s)	Moms	Babysitters	Arias
P. p.	About mom	About babysitter	About aria	About moms	About nannies	About arias

Note!

Nouns of the 1st declension in -iya (ending -я): army, aria, symphony, Maria and others - in the dative case and the prepositional case of the singular have the ending -i, as nouns of the 3rd declension.

Wed: to the army, about the aria, to the symphony, about the symphony, to Mary, about Mary.

On nouns on -ya (ending -я): Marya, liar, cell

Wed: to Mary, about Mary.

2nd declension. masculine

case	Singular			Plural
I. p.	House	Horse	cue	At home	Horses	cues
R. p.	At home	Horse	kiya	houses	horses	Kyiv
D. p.	home	Horse	kyu	home	Horses	qiyam
V. p.	House	Horse	cue	At home	horses	cues
T. p.	home	Horse	Kiem	houses	horses	kiyami
P. p.	About the house	About the horse	About cue	About houses	About horses	About cues

Note!

Nouns of the 2nd declension ending in -y (zero ending): cue, radium, proletarian, planetarium and others - in the only prepositional case they have the ending -i, as nouns of the 3rd declension.

Wed: about radium, about planetarium.

On nouns on -ey, -ay (zero ending): end, sparrow etc. - this rule does not apply (!).

Wed: about the edge, about the sparrow.

2nd declension. Neuter gender

Inflected nouns

case	Singular		Plural
I. p.	Time	Path	Time	Ways
R. p.	time	Ways	times	Ways
D. p.	time	Ways	times	Ways
V. p.	Time	Path	Time	Ways
T. p.	by time	way	From time to time	Ways
P. p.	About the time	About the way	About times	About ways

Note!

In oblique cases, nouns ending in -my have the suffix -en- ( time, seed, name).
Exception make up the plural forms of the genitive case of nouns seed, stirrup - no seeds, no stirrups.