------What's the matter with Tim? ------Oh, Tim's cell phone was left in a taxi accidentally, never ________ again.
Great changes ___ in the city, and a lot of factories ___.
Internet, as well as the telephones, ________ an important part in our daily life.
The value of life lies not in the length of days ,but in the use we ______ them.
Wang Hong is considered ___ one of the best students in our grade.
--- Do you doubt ____ he’ll be fired by the school? --- No, not a bit. But I doubt ____ he will bury himself into study.