Câu hỏi: ......................... any difficulty operating the machine, do not hesitate totelephone our service department.

A. Should you have

B. If you should

C. In case you have

D. Unless you have

Câu 1: Their popularity ................ much more after the Second WorldWar.

A. grew

B. grow

C. is grown

D. has grown

Câu 2: Take John's address with you, ................... you have time to see him whenyou’re in London.

A. if

B. unless

C. in case

D. so long as

Câu 3: Hamburgers ...................... favorite in America in the early century.

A. became

B. becomes

C. has become

D. was become

Câu 4: If it ..................... last weekend, we would have gone skiing.

A. snowed

B. would have snowed

C. had snowed

D. would snow

Câu 5: What would you do if war .......................... ?

A. break out

B. will break out

C. were to break out

D. breaks out

Câu 6: The first hamburgers ..................... in Connecticut in 1895.

A. are sold 

B. were sold

C. sold

D. have been sold