Câu hỏi: Passengers are required to arrive to the gate fifteen minutes before departure time.

A. are required

B. to arrive to

C. before

D. departure time

Câu 1: By measuring the color of a star, astronomers can tell how hot is it.

A. measuring

B. the

C. how

D. is it

Câu 2: When a lion gets hungry, its manner changes and it becomes threatened.

A. when

B. its manner 

C. and

D. threatened

Câu 3: I clearly remember to tell you about this before.

A. clearly

B. remember

C. to tell 

D. about

Câu 4: Although caffeine is a moderately habit-forming drug, coffee is not regarded as harmfully to the average healthy adult.

A. moderately

B. habit-forming

C. harmfully

D. healthy

Câu 5: I was very busy lately since the project of designing the new collection started.

A. was

B. since

C. the project

D. the new collection

Câu 6: It is time the government do something to help the unemployed to find some jobs.

A. do

B. time

C. the unemployed

D. some