1 sentence

1. 在铺设沥青之前，必须确保路面的基层已经夯实。

   zài pū​shè lì​qīng zhī​qián, bì​xū què​bǎo lù​miàn de jī​céng yǐ​jīng hāng​shí.

   Before laying the asphalt, it must be ensured that the subgrade of the road has been compacted.

   Source: Dong Chinese Dictionary