« Instrumental Case (Творительный Падеж)

When to Use the Instrumental Case

• Means or Instrument: Use the instrumental case to describe the means or tool used to perform an action.
  • Example: Он пишет ручкой. (He writes with a pen.)
  • Example: Мы едим ложками. (We eat with spoons.)
• Accompaniment: Use the instrumental case to indicate the person or entity accompanying someone or with whom an action is performed.
  • Example: Я иду с другом. (I am going with a friend.)
  • Example: Она разговаривает с коллегой. (She is talking with a colleague.)
• Means of Communication: Use the instrumental case to express the means of communication.
  • Example: Я написал письмо электронной почтой. (I wrote a letter by email.)
• Profession or Role: Use the instrumental case to indicate someone's profession or role.
  • Example: Он работает врачом. (He works as a doctor.)
  • Example: Она учится студенткой. (She is studying as a student.)

Instrumental Case Endings

The instrumental case is used to indicate the means by which an action is performed or the person with whom something is done. Below is a detailed breakdown of the endings:

Singular Nouns:

• Masculine:
  • For hard-stem nouns, add -ом (e.g., стол → столом - with the table).
  • For soft-stem nouns or those ending in -й, -ь, or a husher (ж, ч, ш, щ, ц), use -ем if unstressed and -ём if stressed (e.g., учитель → учителем - with the teacher, день → днём - during the day).
• Feminine:
  • For nouns ending in -а, use -ой (or rarely -ою) (e.g., книга → книгой - with the book).
  • If the stem of the noun ends in -ц or a husher, replace -а with -ей.
  • If the noun ends in -я (unstressed), replace it with -ей (e.g., неделя → неделей - with the week).
  • If the noun ends in -я (stressed), replace it with -ёй (e.g., семья → семьёй - with the family).
  • If the noun ends in -ь, use -ью (e.g., дочь → дочерью - with the daughter).
• Neuter:
  • Add -м to neuter nouns (e.g., окно → окном - with the window, море → морем - with the sea).

Plural Nouns:

• For hard stems (usually consonants or nouns ending in -а, -о), use -ами (e.g., стол → столами - with the tables).
• For soft stems (including nouns ending in -я, -ь, -е), use -ями (e.g., друзья → друзьями - with the friends).

Adjective Endings:

Adjectives in the instrumental case must agree with the nouns they modify in gender, number, and case:

• Masculine Singular: Ends in -ым or -им (e.g., новым столом - with the new table).
• Feminine Singular: Ends in -ой or -ей (e.g., новой книгой - with the new book).
• Neuter Singular: Ends in -ым or -им (e.g., новым окном - with the new window).
• Plural: Ends in -ыми or -ими (e.g., новыми книгами - with the new books).

Pronouns in the Instrumental Case

• Me: со мной
• You (singular, informal): с тобой
• Him/It: с ним
• Her: с ней
• Us: с нами
• You (plural or formal): с вами
• Them: с ними

Additional Notes

• Adjective Agreement: In the instrumental case, adjectives must agree with the nouns they modify in gender, number, and case.
  • Example: с красивой девушкой (with a beautiful girl)
• Prepositions: Certain prepositions always require the instrumental case, such as с (with), над (over), под (under), между (between), and за (behind, for).
  • Example: Она работает с компьютером. (She works with a computer.)
  • Example: Он сидит за столом. (He sits at the table.)