Bài 1:
Cột trái: garden, green, get, group, game.
Cột phải: school, chemical, call, classroom, kitchen, clean, sick, community, cold, clothes, chemistry, cancel, colour, culture, traffic.
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Bài 2:
1. Have you ever met/ sat
2. did you start/ have recently completed/ asked
3. saw/ have already seen
4. has worked/ started
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Bài 3:
1. was having
2. has travelled
3. haven't begun
4. is running
5. invited/ didn't come
