1. Why have you left the door open? You
will catch cold sitting in the draught.
2. What books did you (read) when
you (lived) in the country?
3. They (haven't yet come) from the south.
4. He (was) ill last week, but now he (has recovered).
5. If everybody
(has read) this new novel, let's discuss it.
6. Have you (booked) tickets? —
Yes, I have. I (booked) them several days ago.