Câu hỏi: Ann is interested in.................... young children.

A. teach

B. teaches

C. to teach

D. teaching

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

A.  has not eaten

B. did not eat

C. is not eating

D. does not eat

Câu 3: Glenda…………..extremely hard when she was a student.

A. worked

B. has worked

C. was working

D. had been worked

Câu 4: Doctors _____ a cure to AIDS yet.

A. have found

B. found

C. haven't found

D. hasn't found

Câu 5: Just keep on................ what you like.

A. do

B. did

C. doing

D. done

Câu 6: He _____ to give up smoking since last week.

A. was trying

B. have tried

C. has tried

D. tried