1. Look! The bird_____(sing) in the tree.

2. Don’t be______(worry). I can help you.

3. Anna often______(go) shopping on the weekend.

4. Kate_______(ride) a bike last Saturday?

5. There______(be) no library in the school twenty years ago.

【答案】1. is singing 2. worried 3. goes 4. rode 5. was

【解析】

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