For example, sound can travel through a pipe if the pipe is full of air molecules, and electrical energy can flow along a wire because the wire is full of movable charges.
(sound; can travel; through a pipe) (the pipe; is; full of air molecules) (electrical energy; can flow; along a wire; because the wire is full of movable charges) (the wire; is; full of movable charges)
sound the pipe electrical energy the wire
can travel is can flow is
through a pipe
full of air molecules
along a wire because the wire is full of movable charges
full of movable charges