2 sentences

1. 他冒充警察在街上巡逻。

   tā mào​chōng jǐng​chá zài jiē shàng xún​luó.

   He impersonated a police officer to patrol the streets.

   Source: Dong Chinese Dictionary

2. 冒充警探就是犯罪。

   mào​chōng jǐng​tàn jiù shì fàn​zuì.

   Impersonating a detective is a crime.

   Source: OpenSubtitles