常用的几种剪纸的方法有（）、（）、（）。
参考答案：阴剪；阳剪；综合法
When you are sleeping, you had better _____ all your windows closed. [ ]
A. don't keep
B. not keep
C. not to keep
D. don't to keep
（2009）静止油面（油面上为大气）下3m深度处的绝对压强为下列哪一项？（油的密度为800kg/m3，当地大气压为100kPa）（）
A.3kPa
B.23.5kPa
C.102.4kPa
D.123.SkPa
