打下手 (dǎ xià shǒu) to help somebody or to act as an assistant

Usage:

“打下手”一般用在口语中，表示“帮忙”或者“给别人当助手”。常用的结构是：给某人打下手。
“打下手”（dǎ xià shǒu） is often used in colloquial language, which indicates helping someone or being as an assistant. It’s often used in the structure of “给某人打下手(gěi mǒurén dǎ xiàshǒu)”.

Sentences:

1、Wǎnshang wǒ xiǎng zàijiā qǐng rén chīfàn, nǐ yàoshi bù máng jiù lái gěi wǒ dǎ xià shǒu ba!
晚上我想在家请人吃饭，你要是不忙就来给我打下手吧！
I will treat someone for supper in my home. Why not help me if you are not busy.

2、Tā xiànzài hái méiyǒu zhèngshì gōngzuò,zài diànli gěi tā māma dǎ xià shǒu ne!
他现在还没有正式工作，在店里给他妈妈打下手呢！
He does not have a job so he is in his mother’s shop as an assistant now.

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