21、You never told us why you were late for the party，( ) ?
A. weren't you
B. didn't you
C. had you
D. did you
22、He's ( ) to know the answer.
A. likely
B. probable
C. maybe
D. probably
22、He's ( ) to know the answer.
A. likely
B. probable
C. maybe
D. probably
24、The heavy snow could not keep us ( ) going out to work.
A. from
B. on
C. upon
D. up
25、They found the lecture hard ( ) .
A. to be understood
B. to understand
C. for understanding
D. to have been understood
26、I learned how to ( ) a bicycle when I was six years olD.
A. drive
B. ride
C. pull
D. draw
29、All the afternoon he worked in his study with the door ( )。
A. to lo ck
B. locking
C. locked
D. lock
30、He is so shy that he ( ) speaks in the publiC.
A. often
B. frequently
C. seldom
D. sometimes
