阅读下面语言材料，完成下面五个句子。

1. You can't talk to the bus driver when __________.

2. Mr. and Mrs. Biggs have to pay _________ for 2 nights.

3. You have to leave your expensive things in _________ in the hotel.

4. ________ people in the store today can meet Yao Ming.

5. Today skaters should go to the local _________.

为了减少机床零部件的热变形，在零部件设计上应注意（）。

A.加大截面积

B.减小长径比

C.采用开式结构

D.采用热对称结构