37. It is six months since John last had his hair cut
It is + time + since + S + last + V(QKĐ)
38. The film which the boys are watching is thrilling
Dùng mệnh đề quan hệ, which để chỉ the film
39. May Day have been considered as a great day by the working people
Bị động thì HTHT: have/has + been + Vpp
40. If there weren't coronavirus outbreak, we could go to the cinema
Câu đk loại 2 để chỉ hđ không thể diễn ra ở hiện tại:
If + thì QKĐ, S + could/would... + V
