Protesters formed 'a human chain' [=they stood next to each other with their arms linked] around the ancient tree to prevent it from being cut down.
In the United States, the President as the commander in chief is at the head of the military 'chain of command'.
I thought he really won the lottery but he was only 'pulling my chain'. [=he was only playing a joke on me]
(..) those was some fairly savage preadolescent jews. No, we were annihilated by our own incompetence and the inability of some people to follow the chain of command. Sheldon, let it go! No, I want to talk about the fact that Wolowitz shot me in the ck. I shot you for good reason. (..)2007 TvShow: The Big Bang Theory Title: The Middle Earth Paradigm Season: 1 Episode 6