问题
选择题
有关图中的描述正确的是
A．a是入射光、b是反射光、c是折射光、QP是法线
B．a是入射光、b是反射光、d是折射光、QP是法线
C．a是入射光、e是反射光、c是折射光、MN是法线
D．a是入射光、b是反射光、e是折射光、QP是法线
答案
答案：B
题目分析： |
| （1）由光路图知，QP与空气和水的界面垂直，因此QP是法线； |
阅读理解
| 任务性阅读。 | |
| |
| It is everyone's duty to protect the environment. Air pollution and 1 pollution are big problems. We should take daily actions to make the pollution 2 senous. We can control the way we choose to live and act on our neighborhood to reduce pollution. For example, if you don't litter here and there, streets will become cleaner. Also, if you don't spit on the gound 3 , the air will become 4 ; and if you ride to work instead of 5 , there will be less air pollution to protect ourselves. So let's do what we can to help protect our living environment. 任务A：用方框内所给的词的适当形式填空，使文章通顺、合理。 1._____ 2.______ 3.______ 4.______ 5.______ 任务B：根据英文释义及首字母提示，拼写单词。 6. s_____ more than two but fewer than many 7. c_____ to enjoy oneself usually for a special reason |