擅自

wǒ shàn zì bǎ chē kāi zǒu le

我擅自把车开走了。

I took the car without permission.

bù kě yǐ shàn zì gǎi biàn cāo zuò guī chéng

不可以擅自改变操作规程。

The operation rules mustn't be changed without permission.

nǐ bù kě yǐ shàn zì zuò jué dìng

你不可以擅自作决定。

You mustn't take upon yourself the right to make decisions.

shàn zì nuó yòng gōng kuǎn

擅自挪用公款

misappropriate the public funds without authorization

shàn zì quē xí

擅自缺席

be absent without leave

shàn zì tái jià

擅自抬价

raise prices without authorization

shàn zì xiū gǎi hé tong

擅自修改合同

unilaterally modify the contract

shàn zì dài bǔ

擅自逮捕

make unwarranted arrest

shàn zì lí qù

擅自离去

leave without notice

shàn zì dòng yòng

擅自动用

take the liberty of using something

shàn zì zuò zhǔ

擅自作主

take an unauthorized action

bù kě yǐ shàn zì pò huài xié yì

不可以擅自破坏协议

cannot unilaterally break the agreement

rèn hé yī fāng dōu bù yǔn xǔ shàn zì xiū gǎi hé tong

任何一方都不允许擅自修改合同。

Neither party may unilaterally modify the contract.