—Excuse me, could you tell me the time, please? —Sorry, I don’t have a watch with me. — ________.
—It’s hard to believe that Jack ________ have fought with the policeman. —Yes. If one ________ ask for trouble, it can't be helped.
___ you lose the paper document, sign in www. Sina.com, __ you might download all you need.
When you read the book, you’d better make a mark _____ you have any questions.
The child tiptoed quietly to the bird. ______ into the forest when he was about to catch it.
He _______ busy yesterday, or he _______ you with your experiment.