兑(duì)

Origin:

“兑”是“悦”的本字，字形的下半是一个人，上半突出了他的嘴和嘴角的笑纹。现在另有“悦”字表示喜悦，“兑”的意思为换取。
“兑” is the original version of the character “悦.” The lower part is a person and the upper part is an exaggeration of a laughing mouth. Today, the character “悦” expresses joyfulness, while the meaning of “兑” is “to exchange.”

Meaning:

exchange; convert; add (water, etc.)

Words:

兑换(duìhuàn): to exchange
兑现(duìxiàn): cash
兑水(duì shuǐ): to water down

Sentences:

1、Wǒ zuòchū de chéngnuò yīdìng huì duìxiàn de.
我做出的承诺一定会兑现的。
I will honor my commitment.

2、Zhè bēi jiǔ shìbúshì duìshuǐ le ？Yīdiǎnr wèidào dōu méiyǒu.
这杯酒是不是兑水了？一点儿味道都没有。
Has this glass of wine been watered down? It has no taste whatsoever.

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