We will have no water to drink _________ we don’t protect the earth.A. until B. if C. unless
The lamb _________already. It_ __________for 2 days.
They’re late. The film _______ for half an hour.
The old man lives ____ in a ____ house, but he doesn’t feel____.
I _______ the book for two weeks. I must return it to the school library.
Miss Yang used _____ a farmer. Now she’s a worker.