Subject + 动手 + (Verb Phrase)
动手 (dòngshǒu) means "to take action," "to start work," or "to strike/hit," depending on context. It literally combines 动 (to move) and 手 (hand). When used positively it means to get started on something; in conflict contexts, it can mean to resort to physical force.
别光说不做,赶紧动手吧。
Bié guāng shuō bù zuò, gǎnjǐn dòngshǒu ba.
Stop just talking without doing anything; hurry up and get to work.
大家一起动手,很快就能收拾完。
Dàjiā yīqǐ dòngshǒu, hěn kuài jiù néng shōushi wán.
If everyone pitches in together, we can tidy up very quickly.
两个人吵着吵着就动手了。
Liǎng gè rén chǎozhe chǎozhe jiù dòngshǒu le.
The two of them argued and argued until it turned into a physical fight.