Câu hỏi: We .............. since 5:00.

A. talk

B. are talking

C. talking

D. have been talking

Câu 1: Barbara .................. that package to you tomorrow morning.

A. deliver

B. is going to deliver

C. are going to deliver

D. delivering

Câu 2: I ................. the house before you called.

A. leave

B. am leaving

C. had left

D. had been leaving

Câu 3: 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

Câu 4: It ............... a lot last winter.

A. snows

B. has been snowing

C. snowed

D. snow

Câu 5: The old drainage pipelines must be maintained; ................, leakage will be unavoidable.

A. therefore

B. similarly 

C. on the contrary

D. otherwise

Câu 6: Before the police arrived, the robbers ..........................

A. run

B. had run

C. have run

D. have been running