Câu hỏi: There was a gradual raise in the number of literate males and females in the lowlands.

A. a gradual

B. raise

C. literate

D. the lowlands

Câu 1: The office manager insists that his staff use all of their vacation time, but he hardly never takes a vacation himself.

A. insists

B. use

C. their

D. hardly never

Câu 2: The big problem was that we really did not understand what was happened

A. problem

B. that

C. did not

D. was happened

Câu 3: A beaver uses its strong front_teeth to cut down trees and peel_off its bark.

A. its

B. front teeth

C. eel off

D. its

Câu 4: Ours brains are incredibly agile machines, and it's hard to think of anything they do more efficient than recognize face.

A. are

B. anything

C. efficient

D. recognize

Câu 5: These snakes will not cause you any serious harm. They are harmful.

A. snakes

B. cause

C. harm

D. harmful

Câu 6: Species like snakes, lizards, coyotes, squirrels, and jack rabbits seems to exist quite happily in the desert.

A. like

B. seems to

C. quite happily

D. the