Câu hỏi: The big problem was that we really did not understand what was happened

A. problem

B. that

C. did not

D. was happened

Câu 1: There was a gradual raise in the number of literate males and females in the lowlands.

A. a gradual

B. raise

C. literate

D. the lowlands

Câu 2: Not one in one hundred children exposed to the disease are likely to develop symptoms of it.

A. not one

B. are

C. symptoms

D. it

Câu 3: Ours brains are incredibly agile machines, and it's hard to think of anything they do more efficient than recognize face.

A. are

B. anything

C. efficient

D. recognize

Câu 4: The eastern bluebird is considered the most attractive bird native of North America by many bird-watchers.

A. bluebird

B. considered

C. native of

D. by

Câu 5: We had better to review this lesson carefully because we will have some questions on it.

A. to review

B. carefully

C. will have

D. on

Câu 6: The sates school system in England can be divided into two levels of educated: primary and secondary

A. be divided

B. into

C. educated

D. secondary