________do you exercise?-I exercise once a day.[ ]

To understand the complex situation completely requires more thought than ________ so far.

Mr. White is my English teacher. He ______ in this school for about 5 years.

It is reported that a small plane from South Africa crashed (坠毁) northwest of Changsha _____ May 28, 2004. [ ]

This is a boy .I don’t know name.