导游警告我们不要靠近灌木丛，那里可能有毒蛇。

The guide warned us not to approach the bushes where ___vipers might be hiding.

小心那个总是奉承你的同事，他其实是个阴险的小人。

Beware of that coworker who always flatters you—he's a real ___viper.