HSK V7-9
Correct

私下

/ sīxià / 
Strokes

Definition

in private

Example

As an Adverb
in private/secret/confidence; privately; secretly
1
Wǒ
我
xiǎng
想
hé
和
tā
他
sīxià
私下
tántán
谈谈
  
。

I wish to talk with him privately. / I wish to talk with him in private.

2
Nā
那
shì
是
biéren
别人
sīxià
私下
gàosù
告诉
wǒ
我
de
的
  
。

I was told about that matter in secret.

3
Sīxià
私下
shāngyì
商议

discuss in private

As an Adverb
without appropriate procedure
4
Sīxià
私下
tiáojiě
调解

intercede unofficially; mediate in private