根据句意和提示写出单词，完成句子，每空一词。
The boy had no difficulty            （解释）the answers to his classmates.
My cousin was busy          （回复）to his pen friend when I came to visit him.
We need ___________(安静)when we are studying in the classroom.
Yao Ming scored 41 points in a game ___________ (对抗)the Atlanta Hawks.
If the man         （拒绝）to leave, call the police.