Correct

出其不意

/ chū qí bùyì / 
Strokes

Definition

to do sth when least expected (idiom); to catch sb off guard

Example

Definition

take sb by surprise; catch sb unawares; beyond one's range of expectation; catch/take sb napping

1
Gōngqíbùbèi
攻其不备
  
,
chūqíbùyì
出其不意
  
。

Attack the unprepared; do the unexpected.

2
Chūqíbùyì
出其不意
dì
地
duì
对
mǒurén
某人
xiàshǒu
下手

catch sb with his pants down