6. The pupils (learn) this lesson when he (come).
7. While Mr. Green (read) the letter, he ( hear) a knock at the door.
8. Where (be) Jack at that time? He ( listen) to the radio in the living-room.
9. Mrs.Wilson (have) an accident while she (drive ) to the work this morning
10. When I (see) them, they (write) some words on the wall.
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