【明報專訊】Putting chewing gum in a machine would undoubtedly cause it to fail. By extension, if something interrupts or stops the normal functioning of a machine, a system, a business or an event, we can say that something has happened to gum up the works. "The sight of a mouse on my new machine frightened me so much that I gummed up the works by spilling oil all over it!" Felix exclaimed.