1840年7月，英国联合哪些国家对穆罕默德·阿里发出最后通牒，要求阿里撤军并承认奥斯曼素丹对埃及的宗主权(     )

①俄国    ②普鲁士   ③奥地利    ④法国    ⑤叙利亚  

用所给词的适当形式填空

①To make a sandwich, we need two ____ (slice) of bread, some vegetables and some meat.

② It rained hard yesterday, but ____ (luck) we brought our raincoats and didn't get wet.

③Ted told us an unusual story ____ (call) Mystery steps.

④ Cindy had fun ____ (make) flashcards with her cousin.

⑤ How old was Laura when she became a ____ (skate) champion?

    Today is Sunday. There's no school. It is sunny. Charlie and his father are going to the park. Look. Charlie is riding his bike. He is very happy. His father is sitting under a big tree. He is reading a newspaper. In the afternoon, the weather is bad. It is cloudy. Now it is raining. Charlie and his father have no umbrella. They are running home. But they forget their bike.

在西部大开发战略中，提出“要努力保护天然林”，大力推行“退耕还林还草”，采取这两种措施的首先目标是（　　）