当你介绍朋友给别人认识,应该说________.A. I'm Mike.B. This is Li Lei.C. He's Li Ming.
South Africa (南非) is acountry.
Columbus __________ America in 1492.
-Have you visited New York? -Yes, I have. I __________ there twice.
Our English teacher __________ to England. She'll come back in ten months. A. have been B. has been C have gone D. has gone
The music made me think of the __________ of a running stream.