关于英语介词题的填空~

关于英语介词题的填空~
1.She felt anxious ( ) her son as she had not heard from him for a long time.
2.You ought to be ashamed ( ) your had manners.
3.Smoking is bad ( ) your health.
4.Be careful ( ) your health.
5.I'm sorry!I'm very bad ( ) expressing myself.
6.Don't you fell sorry ( ) that poor old man?
7.You should knock ( ) the door before you come into the office.
8.The temperature today is eight degrees ( ) freezing-point.
9.I can take my holidays at any time ( ) in August.
10.There is slight difference in meaning ( ) these two sentences.
不会的没关系,空下就行了,19点35分截稿.