đổi sang thể bị động : 1) it was blowing the leaves all over the pavement. 2)Does the hotel provide clean towels? 3)Has someone posted the letter ? 4)They used to start these engines by hand. 5)Why did not they mend the roof before it fell in. chọn từ thích hợp : your sister used to visit you quite often,(didn't she,doesn't she, usedn't she,wouldn't she ?)

1. The leaves were being blown all over the pavement.

(S + tobe + being + V_ed/P2)

2. Are clean towels provided by the hotel?

(Tobe + S + V_ed/P2?)

3. Has the letter been posted?

(Have/Has + S + been + V_ed/P2?)

4. These engines used to be started by hand.

(S + used to + be + V_ed/P2)

5. Why wasn't the roof mended before it fell in?

Chọn từ: didn't she

(Câu hỏi đuôi thì quá khứ đơn:

vế trước khẳng định => vế sau phủ định

used to => didn't

your sister => she)