Вставить предлоги! we often teacher`s the lessons. 2.sometimes they translate instructions 3.did you learn the poem yesterday?

1.We often answer our teacher`s questions at the lessons. 
2.Sometimes they translate instructions from Russian into English 
3.Did you learn the poem by heart yesterday?

1. -, on (первое - пропуск)

2. from, into

3. by