# Phrasal Verb

In the traditional grammar of Modern English, a phrasal verb typically constitutes a single semantic unit consisting of a verb followed by a particle (e.g., turn down, run into, or sit up), sometimes collocated with a preposition (e.g., get together with, run out of, or feed off of). phrasal verbs ordinarily cannot be understood based upon the meanings of the individual parts alone but must be considered as a whole: the meaning is non-compositional and thus unpredictable. phrasal verbs are differentiated from other classifications of multi-word verbs and free combinations by the criteria of idiomaticity, replacement by a single verb, wh-question formation and particle movement.