36. Найдите ошибку в каждом предложении и исправьте её: 1) He didn’t studied Russian. 2) Yesterday we sing the Russian song but we didn’t sing the English song. 3) Where did you saw Oleg? 4) I used to came home at 3 o’clock. 5) I payed the bill two days ago. 6) She use to make a lot of mistakes. 7) — Did you say it to him? — Yes, I did. He understand everything. 8) What do you last Saturday? 9) What is you doing now?

1. He didn’t study Russian.
2. Yesterday we sang the Russian song, but we didn’t sing the English song.
3. Where did you see Oleg?
4. I used to come home at 3 o’clock.
5. I paid the bill two days ago.
6. She used to make a lot of mistakes.
7. — Did you say it to him? — Yes, I did. He understood everything.
8. What did you do last Saturday?
9. What are you doing now?

После didn’t, did и used to используется начальная форма глагола; события в прошлом требуют формы Past Simple, а в вопросе о действии, происходящем сейчас, используется Present Continuous.