按要求改写下列句子。

1. You must do it now. (改为祈使句)

    ______ ______ now.

2. They often play with the cute dog. (用yesterday改写)

    They ______ the cute dog yesterday.

3. Is Lucy writing in English? (用often改写)

    ______ Lucy often ______ in English?

4. They are old teachers. Let us help them. (改为单数句子）

    He is an old teacher. Let ______ help ______.

5. We play basketball every day. (用she来改写句子)

    She ______ basketball every day.