n.愚人，白痴
April Fool's Day 愚人节
I was a fool to trusted her.
我真傻，竟然相信她！ 

vt.愚弄，欺骗
Don't fool me.别骗我。 

vi.干傻事
Stop fooling about with that knife or someone will get hurt.
不要摆弄那把刀, 会伤人的。
[搭配]

make a fool of oneself 做傻事，出丑
"Don't make a fool of yourself, Max," he said.
“别胡闹,麦克思,”他说。 

 make an April fool of sb. 把某人当四月一日愚人节恶作剧的对象
They made an April fool of their English teacher.
愚人节那天他们把英语老师愚弄了一回。 

fool around 游荡，鬼混
He just fools around and does nothing.
他整天游荡，什么事也不做。 

fool away 浪费时间，虚度光阴
Don't fool away your time, there's a lot of work to be done.
别浪费时间啦,要做的事情多着呢。
[谚语]

 A fool may give a wise man counsel. 愚者千虑必有一得。  

 A fool may throw a stone into a well which a hundred wise men cannot pull out.
一个蠢人造成的损失, 一百个聪明人也不能补回。  

 Answer a fool according to his folly.
按照愚人的蠢话回答愚人。  

Better a witty fool than a foolish wit.
宁做聪明的傻子, 不做愚蠢的聪明人。
 
Every man has a fool in his sleeve.
人人都有糊涂的时候。