The girl ran through the forest.
Meaning: This sentence describes the girl's movement as being a quick movement through a large area of land covered with trees.
Choice of Words: Ran means to move quickly by using your legs. Forest is a large area of land covered with trees. When you put them together, "ran through the forest" means that the girl was moving quickly by using her legs through a large area of land covered with trees.
Alternative Expressions
Related Expressions