That is ______ key.

We have been good friends ________ we joined the same ping-pong team.[ ]

Huck, how old is your mother this year? —. And we had a party for her birthday last weekend.

I would appreciatevery much if you could send me a few copies of the mechanic design of your new model.

On the night of February 14th, 2011, all the Chinese _________ by Guo Mingyi, a very common worker who ________ more than 180 poor children since 1994.