用单词或短语替换划线部分的词或短语。 (共6题；每小题1分，满分6分) 

注意：一格不限一词

小题1:To tell the truth, a lot of people want to be rich and famous.   _______________

小题2:The endangered animals he mentioned in his lecture may become extinct any time.

________________

小题3:They completely changed the design. You have no choice but to follow the new one.

________________

小题4:Anyhow, my goal is to supply humans with a life of high quality.

_______________

小题5:Their performances were humorous enough to be followed by other groups. __________________

小题6:It’s a great duty but also a great honor to be chosen as a volunteer for the World Expo.

________________

加热炉管材渗碳目的是提高管材的（）、耐磨性和疲劳强度。

A.硬度

B.强度

C.挠度

D.韧度