----- Nội dung dịch tự động từ ảnh -----
8. She has written this letter for 30 minutes.
=>The letter ..
9. The workers håve taken several steps to whiten the palm leaves.
-> Several steps
10. The students have discussed the pollution problems since last week.
-> The pollution problems ..
11. Somebody has described Keith Jones as the world's greatest guitarist.
-> Keith Jones ...
12. The committee appointed Alice secretary for the meeting.
-> Alice secretary ..