接触电阻存在的时间短暂，一般存在于焊接（）。A、初期 B、中期 C、后期

投资需求的影响因素中不包括( )。

A．产出水平
B．资本成本
C．汇率
D．对将来的预期

Hangzhouhua (杭州话)：use it or lose it

There are about 6.000 languages in the world and some experts say that as many as half of these languages will disappear(消失) in the next one hundred years. Will Hangzhouhua be one of 1)________? It’s a 2)________ that more people are asking.

In China, Putonghua is the official language. That 3)________ it’s the language of government, business and the media (媒体). And it’s also the language that is 4)________ in schools.

Hangzhou is a special city. It used to be the capital of Wu and Yue States in the 10th century during the Five Dynasties period. Now it is modern, fashionable and also beautiful. And Hangzhouhua shows that by being modern, fashionable and beautiful.

Young people still speak Hangzhouhua but not as 5)________ as their parents and grandparents. They are under more and more pressure to speak Putonghua. So the language is being used 6)________ often in everyday life. Some people want to keep the language from disappearing completely 7)_________ building museums and having cultural festivals to save it. But a language isn’t a painting 8)________ a book. It’s a living thing and you 9)________ use it or lose it.

If people 10)________ using it in their daily lives, a museum or a festival will not help. It will be lost forever, like the Yangtze River dolphin.

义齿咬舌的原因与排牙直接有关的是（）

A．人工牙排列偏颊

B．人工牙排列偏舌

C．人工牙排列在牙槽嵴顶

D．人工牙与对颌牙排列成反关系

E．人工牙与对颌牙排列成正常的超覆关系

Do you think it is ____ to throw away glass, metal and paper?[ ]

A. important  

B. necessary  

C. wasteful  

D. impolite

鉴别血尿来源时，当尿中多形红细胞超过尿中红细胞的多少时，可视为肾小球性血尿

A．90%

B．70%

C．30%

D．10%

E．5%