bài 4.
17b 18a 19c ( dòng 3 đoạn 1) 20c ( 2 dòng cuối đoạn 1) 21d ( 2 dòng cuối đoạn 2)
bài 5
22. the film which we are talking about is very exciting
23. neil amstrong was the first person to walk on the moon ( mệnh đề qh có the first, second => dùng to V)
24. the vase broken yesterday by the little boy was very expensive ( rút mệnh đề qh dạng bị động )
25. this is henry whose sister is working for my father
