【推荐3】

am       is       are       was       were

1. Once my sister ________ short. But now she ________ tall.
2. Kitty’s storybook ________ on her desk. Now it ________ (be not) there.
3. —Where are the students?
—They ________ in the music room just now. But they ________ in the playground now.
4. It ________ eight o’clock. The students ________ having lessons..
5. I ________ at a restaurant just now. But now I ________ at home.
6. —Where ________ you last night?   
—I ________ in the supermarket.
7. There ________ some juice in the bottle. Now there ________ nothing in the bottle.