2 sentences for 乘 (chéng — exploit)

1. 乘其不备，掩其不意。

   chéng qí bù bèi, yǎn qí bù yì.

   Catch them off guard and take them by surprise.

   Source: Dong Chinese Dictionary

2. 乘他不注意，我偷偷溜了出去。

   chéng tā bù zhù​yì, wǒ tōu​tōu liū le chū​qù.

   While he wasn't looking, I slipped out.

   Source: Dong Chinese Dictionary