无用

tā zhǐ shì gè wēi bù zú dào de xiǎo rén wù dī jiàn de wú yòng zhī tú

他只是个微不足道的小人物，低贱的无用之徒。

He's a nothing, a low-down, useless nobody.

wǒ men wèi shén me yào láo shén qù zuò zhè xiē wú yòng de shì qing

我们为什么要劳神去做这些无用的事情？

Why should we bother to try to do such useless things?