Câu hỏi: Air pollution, together with littering, are causing many problems in our large, industrial cities today.

A. are

B. industrial

C. problems

D. with

Câu 1: I and Kenny______ pen pal friends since I_______ Singapore.

A. are/ visit

B. were/ have visited

C. were/ visited

D. have been/ visited

Câu 2: I don't mind ______ you ______ the washing up.

A. helping/ doing

B. help/ do

C. to help/ to do

D. helping/ do

Câu 3: Human beings are ________ greatest threat to survival of endangered species.

A. Ø

B. an

C. the

D. a

Câu 4: They_________ Ho Chi Minh City last summer.

A. visit

B. will visit

C. have visit

D. visited

Câu 5: Josh would never forget ________ by his parent through no fault of his own.

A. having scold

B. to have scolded

C. to be scolded

D.  being scolded

Câu 6: Before becoming successful, Charles Kettering, former vice president of General Motors, was so poor that he has to use the hayloft of a barn as a laboratory.

A. as

B. so poor

C. has to

D. successful