Câu hỏi: If it ..................... last weekend, we would have gone skiing.

A. snowed

B. would have snowed

C. had snowed

D. would snow

Câu 1: Exactly .............. we can replace our soil disappearing through erosion is not known.

A. what

B. how

C. if

D. because

Câu 2: A new chairman ................. by our staff.

A. chose

B. was chosen 

C. choose 

D. have been chosen

Câu 3: If you do decide to come, ............................

A. the party’s always a success

B. we would have been so happy

C. I won’t be coming either

D. let me know

Câu 4: Their popularity ................ much more after the Second WorldWar.

A. grew

B. grow

C. is grown

D. has grown

Câu 5: Hamburgers ...................... favorite in America in the early century.

A. became

B. becomes

C. has become

D. was become

Câu 6: What would you do if war .......................... ?

A. break out

B. will break out

C. were to break out

D. breaks out