In the Accusative case, animate and inanimate masluline nouns have different endings. For inanimate masculine nouns, the Accusative and Nominative case endings are the same (see Grammeer Notes to Lesson 4).
But for masculine animate nouns, these endings will be different.
"Антон и Виктор друзья". - "Anton and Victor are friends." "Антон знает Виктора, а Виктор знает Антона". - "Anton knows Victor, and Victor knows Anton."
BUT! In the Accusative case animate feminine singular nouns have the same endings as inanimate ones:
WHEN? DAYS OF THE WEEK
Compare:
Сегодня понедельник.
В понедельник я обычно работаю.
Во вторник, в среду, в четверг и в пятницу я тоже работаю.
Когда я отдыхаю? Я отдыхаю в субботу и в воскресенье.
Вокресенье было вчера. Вчера, в воскресенье, я отдыхал.
SUBJECT OF THOUGHT OR SPEECH
Prepositional Case with the preposition "О" ("about")
The noun which describes an object of thought or speech must be put in the Preposional case with the preposition "o" (about). Usually, such nouns follow the verbs "говорить" (talk about), "думать" (think about", "рассказывать" (tell about", "помнить" (remember about), etc.
"Джон думает о чемодане и о Марии". - "John is thinking about his suitcase and about Maria."
"Джон говорит о Москве". - "John talks about Moscow."
If you need to inquire about a subject of thought or speech, you should start a question with the preposition "О" followed by a pronoun "кто" or "что" in the Prepositional case: О КОМ? О ЧЁМ?
Compare:
Personal pronouns in the Prepositional case have the following forms: