Câu hỏi: It ............... a lot last winter.

A. snows

B. has been snowing

C. snowed

D. snow

Câu 1: I .............. Michael for years.

A. have known

B. know

C. knowing

D. was known

Câu 2: Kevin can’t talk on the phone because he .............. dinner right now.

A. is eating

B. eats

C. has eaten

D. has been eating

Câu 3: I ................. the house before you called.

A. leave

B. am leaving

C. had left

D. had been leaving

Câu 4: The old drainage pipelines must be maintained; ................, leakage will be unavoidable.

A. therefore

B. similarly 

C. on the contrary

D. otherwise

Câu 5: The store ..................... two sales so far this year.

A. is having

B. has been having

C. has

D. has had

Câu 6: We ....................... in the plane for hours when it finally, took off.

A. had been sitting

B. have sat

C. will be sitting

D. will sit