简述金属切削过程中切削热的来源，为减小切削热、降低切削温度，通常可采取哪些撒施？

男性，25岁，反复发作胸闷气促呼吸困难8年余，再次发作5天入院，查体双肺布满哮鸣音，呼气音延长。

在肺功能检查中最不可能的是（）

A.肺活量减少

B.FEV_1.0/FVC%降低

C.MMF降低

D.气速指数>1.0

E.通气改善率为25%

定位当前记录的第一个字段的快捷键是______。

A．Tab

B．Shift + Tab

C．Home

D．Ctrl + Home

人与几种生物细胞色素c的氨基酸差异如下表，其中与人亲缘关系最远的生物是

A．黑猩猩   

B．苍蝇   

C．猕猴    

D．鲨鱼

关于过滤操作的描述，不正确的是（　　）

A．滤纸应紧贴漏斗内壁并用少量水润湿，使滤纸与漏斗壁之间没有气泡

B．漏斗内的过滤液的液面应高于滤纸边缘

C．要沿着玻璃棒慢慢向漏斗中倾倒过滤液

D．漏斗下端管口应紧靠烧杯内壁

动词填空。

1. My uncle with my grandparents ________ (live) in Beijing.

2. Is it time for us ________ (begin) our class?

3. We have fun ________ (swim) in the pool every summer.

4. Mary is clever and can ________ (speak) four languages.

5. I spend about half an hour ________ (chat) with my friends on the Internet.

6. ---Tom, __________(wash) the dishes after supper. 

   ---OK, Mum.

7. Your new friend __________ (sound) good. I want to make friends with him.

8. This pair of shoes________(not be) for Millie. They are for Sandy.

9. Everyone in Mr Wu's class ________ (not do) homework at school.

10. ________ his Chinese and English teachers ________ (come) from the same city?