主动脉系统血管的主干道，将血液由心脏左侧输送到除肺部以外的所有肢体及器官的动脉里
The main trunk of the systemic arteries, carrying blood from the left side of the heart to the arteries of all limbs and organs except the lungs.
树一种多年生木质植物，生有一个主干且常有一个很明显的树冠
A perennial woody plant having a main trunk and usually a distinct crown.
高峰时间最好避免走主干道，一直要等到交通拥挤状况完全消除后才行。
At busy times, it's best to avoid the main roads, and remain clear of them until the worst of the traffic is over.
这个饭店处于两条主干道的交接处，很喧哗。
The hotel is noisy as it stands at the cross of two main roads.
