Questions & Answers about Ребёнок бросил мяч в бассейн.
What case is мяч in, and why does it look the same as its nominative form?
In this sentence мяч is in the accusative case because it’s the direct object of the verb бросил (“threw”). For inanimate masculine nouns like мяч, the accusative form is identical to the nominative form.
What case is бассейн here, and how would it differ if the sentence meant “in the pool” instead of “into the pool”?
Here бассейн is also in the accusative case because в + accusative expresses motion toward something (“into the pool”). If you wanted to say “in the pool” (location), you’d use в + prepositional, i.e. в бассейне.
Why is the verb бросил used instead of бросила, бросило, or бросили?
Past-tense Russian verbs agree in gender and number with the subject. Ребёнок is a masculine noun in singular, so the verb takes the masculine singular ending -л: бросил. If the subject were a girl (e.g. девочка), you’d say бросила; if plural, бросили.
What is the infinitive form of бросил, and what is the difference between бросить and бросать?