Phrasal verbs are two or more words that together act as a completely new verb with a meaning separate from those of the original words.
squash something in
to crush or make something concave by squashing or mashing.
The children squashed the Halloween jack-o'-lantern in and ruined it.
A phrase that combines a verb with a preposition or adverb or both and that functions as a verb whose meaning is different from the combined meanings of the individual words
A compilation of 50 phrasal verbs.