Определите видо-временную форму глаголов в следующих предложениях.
1 The teacher explains new material at every lesson.
2. The teacher is explaining new material now.
3. The teacher has explained new material this week.
4. The teacher has been explaining new material for ten minutes since 9 o'clock in the morning.
5. The teacher explained new material yesterday.
6. The teacher was explaining new material yesterday at 10 o'clock.
7. The teacher had already explained new material when I came to class yesterday.
8. The teacher will explain new material tomorrow.
9. The teacher will have explained new material tomorrow by the end of the first lesson.