【学习目标】
Have students learn some useful new words and expressions about global warming and let them learn effective ways to master them.。
【重点难点】
come about, subscribe; quality; tend; go up ; result in; oppose
【学习内容】
1.come about 发生；造成
有时用it作主语，后面跟that引导的从句
How did it about that he had his leg hurt?
The car accident was horrible but nobody knows how it came about. 这次车祸真可怕，但是没人知道它是怎么造成的。
Many a quarrel has come about through a misunderstanding.
许多争执都是由于误会产生的。
同义词 happen，occur，take place
