Câu hỏi: At times, this can be risky, and the keepers have been injured and one has been killed.

A. good

B. useful

C. healthy

D. secure

Câu 1: They don't seem particularly worried about the situation.

A. concerned

B. pleased

C. frightened

D. excited

Câu 2: She had a cozy little apartment in Boston.

A. uncomfortable

B. dirty

C. lazy

D. warm

Câu 3: The speaker likes to have an attentive audience.

A. neglecting

B. positive

C. active

D. interested

Câu 4: Fish only species that are not of concern, threatened or endangered.

A. educated

B. healed

C. defended

D. brought

Câu 5: How different a picture we now have of the ocean as the sea has begun to reveal its secrets.

A. public

B. opening

C. knowledge

D. schooling

Câu 6: We can do something to save the earth.

A. kick

B. shoot

C. throw

D. destroy