591. You should have a mind of your own． 你必须有自己的主见。

590. Who but Jack would do such a thing? 除了杰克谁会做这种事呢?

589. What he likes best is making jokes． 他最喜欢开玩笑。

588. This is a little something for you． 这是我给你们的一点心意。

587. The price includes postage charges. 价格包括邮资在内。

586. The ice is hard enough to skate on． 冰已经厚得可以划冰了。

585. The book is protected by copyright． 该书受版权保护。

584. Suppose it rains,what shall we do? 万一下雨，我们该怎么办?

583. She became more and more beautiful． 她变得越来越漂亮了。

582. Linda speaks as if she were a boss． 琳达说话总好象她是老板。