They use computers to keep the traffic _________ smoothly.
—Thank you for offering me so much advice on English learning, Tom.—_______ .
He thinks so highly of the movie Avatar that he thinks it is worth seeing ______ second time.
It was probably _______ the wrong operation(操作) of the pilot that caused the plane to crash.
—I’m your old friend Tom. We used to study in the same high school. —Tom? I’m sorry I ______ you. Where have you been all these years?
Come on!Tell us ______ you remember about what happened then.