Câu hỏi: UFOs mean ................flying objects.

A. unknown

B. unidentified

C. unable

D. unimaginary

Câu 1: How many countries took part in the first World Cup?

A. interested

B. participated

C. competed

D. cooperated

Câu 2: Many people become ..................because of the natural disaster every year.

A. homeland

B. homesick

C. homeless

D. homework

Câu 3: The existence of different kinds of animals and plants which make a balanced environment is called........

A. biodiversity

B. rubbish

C. challenge

D. maintain

Câu 4: Some whales migrate into warm waters to bear their.............

A. young 

B. diets

C. calves

D. young whales

Câu 5: Some tiny organisms are..........along by the currents.

A. carried

B. taken

C. flowed

D. beside

Câu 6: According to the weather..............it will be raining tonight.

A. forecast

B. forecaster

C. forecasted

D. forecasting