The teacher asked all the students in the class to keep their eyes ______.

A. to be based on

B. to base on

C. which to base on

D. on which to base

A. never had felt tired

B. had never felt tired

C. never felt tired

D. was tired neve

A. in which

B. that

C. where

D. on which

A. rain

B. will rain

C. raining

D. rains

A. which

B. what

C. where

D. /

A. get up

B. getting up

C. gets up

D. got

A. has

B. are being

C. is

D. are

A. would have lost

B. should lose

C. might lose

D. could have lost

A. What；what

B. What；that

C. That；that

D. That；what

A. in front of

B. in the front of

C. at the back of

D. at the beginning of