他被蒙在鼓里，完全不知道发生了什么。
tā bèi mēng zài gǔ lǐ ， wánquán bùzhīdào fāshēng le shénme 。
He was kept in the dark and had no idea what was happening.
我们在雨中蒙了个湿透。
wǒmen zài yǔzhōng mēng le gè shī tòu 。
We got completely soaked in the rain.
他在比赛中蒙了对手。
tāzài bǐsài zhōng mēng le duìshǒu 。
He caught his opponent off guard in the competition.