To do some voluntary work for the 2nd Youth Olympic Games is ______ excellent chance for us to serve our hometown—Nanjing.

She looked at the professor and wondered where she_______ him.

Boy, you _______ lean (伸) out of the window while the bus is running. That’s dangerous.—Sorry, I won’t do that again.

This physics problem is too difficult. Can you show me __________, Wang Lin?— Sure.

An accident ________ on Zhongshan Road yesterday afternoon.