2 sentences

1. 警察挨家挨户地调查案情。

   jǐng​chá āi​jiā'āi​hù de diào​chá àn​qíng.

   The police investigated the case house by house.

   Source: Dong Chinese Dictionary

2. 邮递员正在挨家挨户送信。

   yóu​dì​yuán zhèng​zài āi​jiā'āi​hù sòng​xìn.

   The mailman is delivering mail door-to-door.

   Source: Dong Chinese Dictionary