Câu hỏi: Doctors _____ a cure to AIDS yet.

A. have found

B. found

C. haven't found

D. hasn't found

Câu 1: Fish were among the earliest form of life. Fish ………….. on earth for ages and ages.

A. existed

B. are existing

C. have existed

D. exist

Câu 2: He _____ to give up smoking since last week.

A. was trying

B. have tried

C. has tried

D. tried

Câu 3: I'd like to borrow this book. .................................. it yet?

A. Did you read

B. Had you read

C. Have you read

D. Do you read

Câu 4: No breakfast for Mark, thanks. He…………..breakfast.

A.  has not eaten

B. did not eat

C. is not eating

D. does not eat

Câu 5: No, you can’t go to holiday by yourself! You aren’t . . . . . . . . . . . . !

A. very old

B. too old

C. old enough

D. enough old

Câu 6: According to the research reports, people usually ………….. in their sleep 25 to 30 times each night.

A. turn

B. are turning

C. have turned

D. turned