以假乱真
Pass off a fake as real

jiǎluànzhēn
Pass off a fake as real

Chinese Idiom 以假乱真 yǐ jiǎ luàn zhēn
Here’s a breakdown of the characters in 以假乱真(yǐ jiǎ luàn zhēn):
以(yǐ): formal way to say “to use”

假(jiǎ): fake

乱(luàn): to confuse or mix up ( 混乱 - hùn luàn)

真(zhēn): genuine or real (真货 - zhēn huò )

It’s not easy being a young, single guy in China.
You live in the era of the 3 highs (三高时代 sān gāo shí dài).
And you have to go home for Spring Festival -- where relatives look forward to meeting your nonexistent girlfriend!
Some Chinese online shopping sites see this as an opportunity, letting you rent someone to pretend to be your girlfriend, and save you from embarrassment.
That’s assuming you can pull it o -- that you can successfully 以假乱真(yǐ jiǎ luàn zhēn).
以假乱真means to take something that’s fake and try to pass it o as real. It can also mean to take something that’s fake and mix it among real things.

“有时候真的不得不佩服这些山寨厂商,模仿也可以以假乱真,功力不浅”
“yǒu shí hou zhēn de bù dé bù pèi fú zhè xiē shān zhài chǎng shāng, mó fǎng yě kě yǐ yǐ jiǎ luàn zhēn, gōng lì bù qiǎn”
“Sometimes you can’t help but respect these shanzhai manufacturers -- they’re able to pass off fake things as real, and their skills are considerable”

“这里的配件和包装足以达到以假乱真的地步”
“zhè lǐ de pèi jiàn hé bāo zhuāng zú yǐ dá dào yǐ jiǎ luàn zhēn de dì bù“
“The parts and packaging has already reached the level of being able to pass itself off as real”

“私自勾兑的假酒真的能以假乱真吗?”
“sī zì gōu duì de jiǎ jiǔ zhēn de néng yǐ jiǎ luàn zhēn ma?”
“Is privately blended fake alcohol really able to pass itself off as real?”

“一个以假乱真的记者证,街头只要数 百元就可以买到”
“yí gè yǐ jiǎ luàn zhēn de jì zhě zhèng, jiē tóu zhǐ yào shù bǎi yuán jiù kě yǐ mǎi dào“
“A real looking journalist license and title can be bought for just a few hundred yuan”

不鸣则已,一鸣惊人
Amazing the World with a Single Feat