18. Our teachers have explained the English grammar.
A. The English grammar was explained by our teachers.
B. The English grammar has been explained by our teachers.
C. The English grammar have been explained by our teachers.
D. The English grammar has not been explained before.
19. "If you visit Hanoi, you should go to Hoan Kiem Lake.", my friend told me.
A. My friend suggested that I should go to Hoan Kiem Lake if I visited Hanoi.
B. My friend suggested that you should go to Hoan Kiem Lake if you visit Hanoi.
C. My friend suggested that go to Hoan Kiem Lake if I visited Hanoi.
D. My suggested that going to Hoan Kiem Lake if I visited Hanoi,
20. The detective saw the woman putting the jewelry in her bag.
A. The jewelry was put in the woman's bag by the detective.
B. The woman was saw by the detective put the jewelry in her bag.
C. The woman was seen the detective putting jewelry in her bag.
D. The woman was seen putting the jewelry in her bag by the detective.