Which part of a tractor-trailer is the tractor, and which is the trailer? What kinds of things do these trucks carry? Young readers discover the answers to these questions and many more as they learn about these huge trucks. Tractor-trailers are familiar vehicles, and young readers learn new information about them with every turn of the page. Strong picture-text correlation throughout this high-interest volume helps develop comprehension skills. Simple, accessible text is paired with colorful images of tractor-trailers on the road, drawing in young readers who love big trucks.