Correct

瞒得过初一,瞒不过十五

/ mán dé guò chū yī mán bù guò shí wǔ /
Strokes
https://i.cchatty2.com/filters:format(webp)/fit-in/684x0/img/202102/瞒得过初一瞒不过十五-Chinese-idioms-Cchatty-59af660d-856a-4266-a73f-8e8397330eed-1612777851.jpg

Collocation

1
即使瞒得过初瞒得过初一,瞒不过十五,也瞒不过十五
2
这事情瞒得过初一,瞒不过十五

Definition

瞒得过初一,瞒不过十五

Literally means:

can not deceive the first day, but fifteen

Actually means:

you can cheat people for a time but not for all the time

It means that you can cover the truth for a time, but the truth will be exposed sooner or later. Metaphorically, it means that truth is not something to be hidden. It is often used to persuade others to tell the truth.

就算现在把事情隐瞒下来了,以后真相还是会暴露的。比喻事情终究隐瞒不住。常用来劝告别人说出真相。

Example

Used as a minor sentence, or as predicate. It can be used with other words in between. (作小句、谓语,中间可以插人其他词语)
1
Mán
de
guò
chū
初一
  
,
mán
guò
不过
shí
十五
  
,
chízǎo
迟早
huì
zhīdào
知道
shi
de
qīnshēng
亲生
qīn
母亲
de
  
,
不如
zǎodiǎn
早点
de
shēnshì
身世
gào
告诉
  

To hide from the first day, not to hide fifteen, sooner or later she will know that you are not her own mother, it is better to tell her about her life earlier.

2
Jǐnguǎn
尽管
di
弟弟
nàn
遇难
de
shì
mán
de
guò
chū
初一
  
,
mán
guò
不过
shí
十五
  
,
dànshì
但是
yuàn
愿意
ràng
父母
shāngxīn
伤心
  
,
suǒ
所以
zhí
一直
gǎn
gào
告诉
liǎng
wèi
lǎorén
老人
  

Although his brother's death was not hidden from the first day, but not fifteen, but he did not want to let his parents sad, so has been afraid to tell the two old people.

3
háishi
还是
ba
爸爸
de
bìngqíng
病情
gào
告诉
ma
妈妈
  
,
mán
de
guò
chū
初一
  
,
mán
guò
不过
shí
十五
  
,
zhè
shì
zuìzhōng
最终
háishi
还是
huì
zhīdào
知道
de
  

You'd better tell your father's illness to your mother, hide it from the first day, hide it from fifteen, and she'll know about it eventually.