Some aspects of a pilot’s job__________ be boring, and pilots often ________ work at inconvenient hours．

You were stupid to try climbing up there. You ______ yourself.

English is a language that many people around the world _______not speak perfectly but _________at least understand．

A hard-working man        become a great scientist, but a great scientist        be a hard-working man.

—Did you visit the museum last week? —No, we _____, but we spent too much time shopping.