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]
(..) Where could he be at this hour? l'd better go out again and look for him. And remember, nobody eats a bite until l fi nd him. lgot-a no strings but lgot-a the brain lbuy a newsuit andlswing-a the chain leat-a the best andldrink-a champagne lgot-a no strings on me - Bravo, Pinocchio! - They like me. (..)1940 Pinocchio