One day, Tina sat on the 小题1:__________ and watched hermother do the dishes in the 小题2:_________ . Tina noticed thather mother had some 小题3:         hairs on her head. She looked at her mother and 小题4:__________ , “Why do you havesome white hairs, Mom?” Her mother answered, “Well, every time you do somethingwrong and make me 小题5:___________ , one hair turns white. If you don’t make me sad any more, I will have black小题6:__________.”

The little 小题7:__________ thought for a while and then said, “Mom, I am going to listen to your words carefully from today on and I would like to be a 小题8:_________ kid. Then you will not have so many white hairs, will you?” Her mother smiled and nodded（点头）.

Tina’s grandma was 小题9:_________TV in the living room. Tina glanced（看一眼）at her grandma and asked, “Mom, why is 小题10:_________ hair all white? Her children aren’t good ones, are they?”

纯钛铸件铸造后采用哪一种冷却方式比较好

A．室温下慢慢冷却

B．热水冷却

C．凉水中快速冷却

D．室内放置0.5h后再用凉水冷却

E．室内放置1h后再用凉水冷却