1 sentence

1. 建筑工人在高空进行作业时必须戴安全帽。

   jiàn​zhù​gōng​rén zài gāo​kōng jìn​xíng zuò​yè shí bì​xū dài ān​quán​mào.

   Construction workers must wear safety helmets when working at heights.

   Source: Dong Chinese Dictionary