红外光谱制样技术中要用到溴化钾片的是()()()。
参考答案:压片法;糊法;膜法
说说近百年来中国美学思想发展轨迹。
用单词的适当形式填空。
1. He is 10 ___ (year) old.
2. His father often ______ (relax) for half an hour after lunch.
3.There are many green ______ (leaf) on the tree in summer.
4. Molly likes ___ (play) with her friends and eats ____ (grass).
5. Bill usually ______ (sleep) during the day.