April Fools' Day is called 愚人节 (yúrén jié). 节 (jié) stands for a holiday or a festival. 愚人 (yúrén) is the abbreviation of 愚笨的人 (yúbèn de rén), which means a foolish person, or a fool.
愚蠢 (yúchǔn), 愚笨 (yúbèn) and 笨 (bèn) all mean stupid or foolish.
呆 (dāi) means dim-witted or wooden-headed.
傻 (shǎ) means stupid or muddle-headed.
Therefore, there are a few additional ways of saying "a fool".
傻子 (shǎzi) A foolish person.
呆子 (dāizi) A dim-witted person.
傻瓜 (shǎguā) A foolish melon.
笨瓜 (bènguā) A stupid melon.
呆瓜 (dāiguā) A dim-witted melon (a wooden head).
笨蛋 (bèndàn) A stupid egg.
You can tell from the above examples that the Chinese don't hold melons and eggs in high esteem. While a parent may say "小傻瓜 (xiǎo shǎguā little fool)", to his or her own child in an endearing way, please don't call anyone a melon or, worse, an egg.
Of course, all of us want to be regarded as being intelligent and smart.
聪明 (cōngmíng) means intelligent or sharp.
伶俐 (línglì) means clever or quick-witted
头脑好 (tóunǎo hǎo) means to have (good) brains.
脑筋好 (nǎojīn hǎo) means to have a good mind.
有智慧 (yǒu zhìhuì) means to possess wisdom.
Correspondingly, you may refer to a bright person as follows:
聪明的人 (cōngmíng de rén) An intelligent person.
伶俐的人 (línglì de rén) A clever or quick-witted person.
头脑好的人 (tóunǎo hǎo de rén) A smart person.
脑筋好的人 (nǎojīn hǎo de rén) An intelligent person.
有智慧的人 (yǒu zhìhuì de rén) A wise person.
智者 (zhì zhě) A sage. The word 者 is a formal word used to refer to a person.
The Chinese word for IQ, the Intelligence Quotient, is 智商 (zhìshāng). I believe that, whatever IQ you start with, the process of learning a new skill, such as a foreign language, will add a few points to your malleable intelligence and education quotient.
By the way, if you're inclined to play an April Fools' joke on someone, be sure to say this afterwards:
wǒ zhǐshì kāi ge wánxiào de.
I'm only joking.
Hopefully, you will get this gracious response:
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