Listen! There is a knock on the door. Who_____ it be—It must be Jack. Just now I sent for him.

David has made great progress recently.—- ________ and ________.

The medical team ____ five doctors and ten nurses is to be sent to Wenchuan.

Your aunt often walks the dog in the morning.— Yeah, ___________ bad weather stops her.

try to understand ____ that prevents so manyAmericans from being as happy as one might expect, it seems to me that thereare two causes.