Câu hỏi:

But we can stop adding the problem while scientists search for answers, and laws are passed in nature’s defense.

A. frisk

B. rifle

C. track

D. examine

Câu 1:

Each year about fifty hundred species of plants and animals are already being eliminated.

A.  dropped

B. removed

C.  kicked

D.  tossed

Câu 2:

Work on the production line is monotonous and lacks _______.

A.  variety

B.  various

C.  varied

D.  variable

Câu 3:

He says he'll tell the authorities but it's just an empty ______.

A.  threat

B.  threaten

C.  threatening

D.  threateningly

Câu 4:

A healthy body will be able to fight off the illness _______ without the use of medicine

A. nature

B. natural

C. naturalize

D. naturally

Câu 5:

Choose the word whose underlined part has a different pronunciation from the others in each group

A. pollute

B. develop

C. constant

D. provide

Câu 6:

Choose the word whose main stress is placed differently from the others in each group

A. illness

B. slowly

C. spoken

D. police