VOA慢速英语:Too Much Internet May Be Bad for Teenagers

train has left the station – idiomatic expression (another way to say this is “that ship has sailed”)

blood vessels ­– n. a small tube that carries blood to different parts of a person or animal's body

strain ­– v. to injure by overuse, misuse, or excessive pressure

consume – v. to absorb completely; engross or obsess