Câu hỏi: We are very grateful to Professor Humble for his generosity in donating this wonderful painting to the museum.

A. meanness

B. sympathy

C. gratitude

D. churlishness

Câu 1: She wrote me a vicious letter.

A. helpful

B. gently

C. dangerous

D. healthy

Câu 2: Solar energy is not only plentiful but also infinite.

A. without limit

B. boundless

C. limited

D. indefinite

Câu 3: We'd better speed up if we want to get there in time.

A. slow down

B. turn down

C. put down

D. lie down

Câu 4: ‘What I’ve got to say to you now is strictly off the record and most certainly not for publication,’ said the government official to the reporter.

A. already official

B. beside the point

C. not popular

D. not recorded

Câu 5: She is a very generous old woman. She has given most of her wealth to a charity organization.

A. mean

B. amicable

C. kind

D. hospitable

Câu 6: Population growth rates vary among regions and even among countries within the same region.

A. restrain

B. stay unchanged

C. remain unstable

D. fluctuate