"April fool"是与西方传统节日相关的常用表达，英式音标为/ˌeɪ.prəl ˈfuːl/，美式音标为/ˌeɪ.prəl ˈfuːl/。作为名词，它有两个核心含义：一是指"愚人节中受愚弄的人"，二是指"愚人节当天的愚弄行为"。在实际使用中，这个短语通常与April Fools' Day（愚人节）紧密关联，后者的正确写法存在两种形式——牛津词典收录为April Fool's Day，而美国传统词典和韦氏词典则优先采用April Fools' Day，但两者在日常语境中均可通用。

用法解析：

作名词指受愚弄者
当某人在4月1日被恶作剧时，即可称为"April fool"。例如："Greg was waiting outside ready to shout, 'April fool!'"（格雷等在外面准备大喊："上当啦！"）。在法国文化中，受愚弄者还被称为"April fish"（上钩的鱼），这一说法源于四月幼鱼易上钩的隐喻。

作感叹语表示玩笑揭晓
在完成恶作剧后，施动者常以"April fool!"作为结束语，宣告玩笑的真实性。例如："Then Kunfuth grinned and shouted 'April Fools!'"（然后孔富思咧嘴笑着喊道："愚人节玩笑！"）。

相关短语搭配

play an April Fools' joke on sb：对某人开愚人节玩笑。如"The headmaster decided to play an April Fools' joke on the students"（校长决定对学生们开个愚人节玩笑）。

pull a prank：进行恶作剧。"You may laugh at a prank on April Fools' Day"（你可能会为愚人节的恶作剧发笑）。

April Fools' Day：愚人节的标准名称，指4月1日这个以互相捉弄为乐的节日。

例句10句：

She told me the school was closed today, but it was just an April fool.

When I realized I'd been tricked, my friend yelled, "April fool!"

Don't be an April fool—check the date before believing strange news today.

The TV station announced a fake alien invasion as an April fool.

He tried to convince me I'd won the lottery, but I knew it was an April fool.

In France, people might call you "April fish" instead of "April fool."

My brother glued my shoes to the floor as an April fool.

The newspaper printed a ridiculous story as an April fool's joke.

We planned an April fool on our teacher by hiding all the chalk.

She looked embarrassed when we shouted, "April fool!" after her prank failed.

从文化角度看，"April fool"的起源可追溯至16世纪法国历法改革——坚持在4月1日庆祝新年的守旧者被革新派嘲笑为"April fools"，这一传统逐渐演变为如今的愚人节。尽管这一表达带有"愚弄"的字面含义，但在实际使用中通常不含恶意，而是强调节日的轻松幽默氛围。下次愚人节遇到玩笑时，不妨用"April fool!"回应，感受跨文化的语言趣味。