He apologized ________ late．

1. A.
   to his teacher to arrive
2. B.
   to his teacher for arriving
3. C.
   at his teacher to arrive
4. D.
   at his teacher for arriving

He apologized ________ late.

A. to his teacher to arrive　 B. to his teacher for arriving

C. at his teacher to arrive　 D. at his teacher for arriving

He apologized ________ late.

He apologized ________ late.

A. to his teacher to arrive                 B. to his teacher for arriving

C. at his teacher to arrive                 D. at his teacher for arriving

21. He apologized ________ late.