Like any highway system, the federal airways have their main trunk line.

同任何公路系统一样，联邦航空线路也有其主航线。

youdao

Digital trunk system. Yeah. Jack. Yeah.

数字中继系统。对。杰克。你说。

youdao

Trunk and Facilities Maintenance System?

中继线设备维护系统TFMS ？

youdao

Trunk and Facilities Maintenance System?

中继线设备维护系统TFMS ？

youdao