门（mén）

Origin:

甲骨文的“门”是两扇门的样子，十分形象。简体字把它精简成了门框的样子。后来“门”也有途径、诀窍、分类的意思，一些负面的事件可以说“XX门”，比如美国的水门事件。
On oracle bone inscriptions, the character “门” looks like a pair of doors; it was later simplified to its appearance more like a doorframe. Later, it also came to mean a way of doing something, a secret to success, or a classification. It can also be used as “XX 门” to describe scandals like Watergate (水门).

Meaning：
door, way of doing something, secret or knack, classification
Words：
开门(kāi mén): to open a door
敲门(qiāo mén): to knock (on the door)
窍门(qiàomén): knack
水门(Shuǐmén): Watergate
分门别类(fēn mén bié lèi):to arrange

Sentences：

1、Zuò shìqing yào yǒu qiàomén，zhèyàng cái bú huì làngfèi shíjiān.
做事情要有窍门，这样才不会浪费时间。
One should have a knack for doing things so as not to waste time.

2、Tā xíguàn bǎ dōngxi fēn mén bié lèi fàng hǎo， zhèyàng bǐjiào yǒu tiáolǐ.
他习惯把东西分门别类放好，这样比较有条理。
He is used to arranging things, which is quite orderly.

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