trunk roadway

例句：

1. 1. The main road runs through the heart of the city.
   这条主干道穿过市中心。
2. 2. The trunk highway connects two major cities.
   这条主线道路连接了两个主要城市。
3. 3. The construction of the trunk road has greatly improved traffic flow.
   这条主线道路的建设极大地改善了交通流量。