JZ250型悬重表死绳固定器的传感器间隙要保持在（）。A、15~20mm B、8~1

______ speaking(一般来说), parents care more about their children’s health than about their own.

根据句意和中文意思或所给词，写出正确的单词。

1. You are ______ (suppose) to shake hands when you meet a Chinese friend.

2. Keep your eyes ______(close) when you are doing eye exercises.

3. A knife is used for _______(cut) things.

4. Trees can keep water from _______ (run) away.

5. Everything was ______( familiar ) with me because I was in Japan for the first time?

6. Do you still remember______(看见) me somewhere in Beijing ?

7. Give up bad _________ (举止) and be polite.

8. ________ ( 花 ) time with family and friends is very important.

9. He is _________ (满意)with his son.

10. People are pretty _______( 宽松 ) about time in Colombia.

—What's the woman in a white hat?

—__________. [ ]

A. She is my teacher

B. She is a cook

C. She is thirty

D. She is a girl

下列溶液的最大的是

A．石灰水

B．食醋

C．自来水

D．汽水

材料：2011年9月29日，中国首个空间实验室“天宫一号”在酒泉卫星发射中心成功发射。它标志着我国空间实验站技术的探索有了重大的突破。而这之前，我们已经经历了从“神一”到“神七”，“嫦娥一号”到“嫦娥二号”等多次实验，可以说这些科学实践为“天宫一号”的成功发射奠定了坚实的基础。然而，这还只是第一步，“神八”飞船也将于11月升空。“天宫一号”与“神八”并将于2012年完成交会对接试验。我国还将通过多次发射，建立真正空间站；再向前发展，中国人登上月球甚至火星，也将不是一个梦想。

上述材料中如何体现实践是认识的基础?