Câu hỏi: Scientists sent ............ expedition to ............ Mars during .......... 1990s.

A. an/  X/  the

B. an/  the/  the

C. X/  X/  the

D. X/  X/  X

Câu 1: .............. winter is usually cold, but .................. winter of this year is warm.

A. the/  X

B. X/  the

C. the/  the

D. X/  X

Câu 2: ......... chair which you are sitting in is broken.

A. a

B. an

C. the

D. x

Câu 3: He usually travels to..................Philadelphia by.................. train.

A. the/  X

B. X/  the

C. the/  the

D. X/  X

Câu 4: I'm on night duty. When you go to ..............bed, I go to ............ work.

A. the/  X

B. X/  the

C. the/  the

D. X/  X

Câu 5: Rita is studying........... English and ...........math this semester.

A. the/  X

B. X/  the

C. the/  the  

D. X/  X

Câu 6: Every year, thousands of tourists visit ……... Nile River.

A. a

B. an

C. the

D. x