【1】chain  n. 一系列，一连串人或事(英语解释a series of connected things or people;A chain of things is a group of them existing or arranged in a line.)

 Students tried to form a human chain around the parliament.  

学生们试图在议会四周围成人墙。

Volunteers formed a human chain to rescue precious items from the burning house.

志愿者排成一条长龙，从着火的房子里手传手把贵重物品抢救出来。