热身：先来读读这些短语和句子，对cloud有个初步的认识
a cloud of dust. 一团沙土
a black mass of cloud.一团乌云
cloud one’s vision 蒙蔽了某人的眼睛
be lost in the clouds 如坠五里云雾中，茫然不知所措；空想
The mirror clouded.镜子起雾了。
A cloud drifted by and covered the moon. 飘过来一片云彩挡住了月亮。
Her eyes were clouded with tears. 她泪眼婆娑。
The sunny sky suddenly clouded. 晴朗的天空突然阴云密布。
His brow clouded with anger. 他眉宇之间怒气横生。
be on cloud nine 高兴极了；异常兴奋；乐不可支
---"Was Helen pleased about getting that job?"
---"Pleased? She was on cloud nine!"
---“海伦得到那份工作高兴吗？”
---“岂止是高兴？她简直飘飘然了！”
be under a cloud 不被信任，受怀疑；受嫌弃，不受欢迎The cabinet minister left office under a cloud after a fraud scandal.
这位内阁大臣因涉嫌诈骗丑闻而离职。
a cloud hanging over sb 有心事；不悦；忧心忡忡When you're waiting for an operation, you feel like there's a cloud hanging over you.
等待手术的时候，会感觉忧心忡忡的。
a cloud on the horizon 可能到来的麻烦；令人担忧的事The only cloud on the horizon is the physics exam in June.
唯一要担心的就是6月份的物理考试。
Every cloud has a silver lining黑暗中总有一线光明。I got laid off from work yesterday, but every cloud has a silver lining and now I can spend moretime writing my book.
昨天我被解雇了，但事情总有好的一面，现在我有更多的时间可以写书了。
have one's head in the clouds 想入非非，心不在焉"Alice, do you have your head in the clouds?"asked the teacher. She is absent-minded all day in the class. She must be in love.
“爱丽丝，做什么白日梦呢？”老师问。她在课堂上整天都心不在焉的，一定是恋爱了。
