对旅游目的地国家或地区及其旅游经营者来说，旅游资源的主要功能表现在娱乐健身、增知益神、观赏消闲。( )
参考答案：错
根据首字母或汉意填空，每空一词。
1. Zhu used to be shy, but now he is o______.
2. I don't like making speeches. I feel n______ talking in front of many people.
3. When I began to sing，he laughed and made me very ______ (尴尬的).
4. After a long trip to Europe, I felt very ______(精疲力竭的).
5. Last night a friend of mine invited me to a ______ party (化装舞会).
石油裂解制取乙烯时，为了获得较高的乙烯收率，常采用的措施是什么？为什么？
