主幹線

trunk line (of road, network etc) / backbone (cable)

owner / master / host / individual or party concerned / God / Lord / main / to indicate or signify / trump card (in card games)

trunk / main / core

tree trunk / main part of sth / to manage / to work / to do / capable / cadre / to kill (slang) / to fuck (vulgar) / (coll.) pissed off / annoyed

main line / trunk line

thread / string / wire / line / CL:條|条[tiao2],股[gu3],根[gen1] / (after a number) tier (unofficial ranking of a Chinese city)