Practice Russian the friendly way — with free, interactive exercises. Work through grammar, vocabulary, and reading by topic and level, and check your answers as you go.
Going back to the singular is harder than making the plural: you need to know the word itself, not just the rule. It’s good practice for your feel for gender, and for looking up the plurals you meet in texts, since dictionaries list nouns in the singular.
Practice turning Russian nouns into the plural: regular endings for all three genders, plus the forms you learn one by one — дома, братья, люди, дети.
Обо́их, обе́им, обе́ими — pick the form the sentence needs, and put the noun with it.
Pick о́ба or о́бе by gender, then put the noun and any adjective into the right form.
Not every both is о́ба. Choose the Russian that matches the English: и…, и…, и то, и друго́е, ни…, ни…
Two decisions in every sentence: which of the three prepositions belongs in the gap, and what form the word in brackets takes after it. No verbs of motion here — nothing is going anywhere. Your clue is what the sentence is actually about: a place, a channel, or a subject.
No hints in brackets. Each sentence tells you who or what it is about — work it out, then put the pronoun into the instrumental.
Two decisions in every sentence: which ending the word needs, and whether с belongs in front of it. English gives you with for both, so this is the one place Russian asks you to think about something your own language never made you notice.
No hints in brackets this time. Each sentence tells you who it is about — your job is to work that out and put the right personal pronoun into the prepositional case. The preposition is already waiting for you.
Where is it, and where did it happen? Every sentence needs в or на plus the prepositional form of the word in brackets — and the words are not all singular, so keep an eye on the endings.
Every question word — кто, что, какой, как, где, когда — choose -то, -нибудь, or угодно, and decline where the sentence needs it.
Practice choosing какой-то, какой-нибудь, or какой угодно in Russian, declined to agree with the noun.