墙头草 (qiángtóu cǎo) fence-sitter; a person who follows the crowd; floater

Usage:

墙头草是指长在墙头上的草,风往哪里吹它就往哪里倒。用来比喻那些没有主见的人,哪边得势,哪边比较强,他就倒向哪边。这些人完全没有自己的立场,随外界情势的变化而变换态度。
The grass on the top of a wall sways with wind. This word is used to refer to a person who doesn’t have his own view. That kind of people who bend to the powerful side usually change their minds according to the realities of the situation.

Sentences:

1、Wǒmen zuòshì yīnggāi jiānchí zìjǐ zhèngquè de kànfǎ, bùnéng zuò qiángtóu cǎo.

我们做事应该坚持自己正确的看法,不能做墙头草。

We should hold to our own right views, and mustn’t become floaters.

2、Tā zhègè rén shuí lìhai jiù tīng shuí de ,zhēn shì gè qiángtóu cǎo.
他这个人谁厉害就听谁的,真是个墙头草!
He always follows to the person who is more powerful, what a fence-sitter!

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