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----- Nội dung dịch tự động từ ảnh -----
17. It was
expensive car that he couldn't afford to buy it.
.... ..
a. so
b. very
c. such a
d. such an
18. I didn't have time to study
I failed the exam.
.... ..
a. since
b. because
C. sO
d. so that
19. They first met ...they were at high school.
a. since
b. when
c. while
d. for
20. I find this math problem difficult. If only brother
....here to help me.
а. is
b. were
c. be
d. being