答案:Phrasal verbs are idioms which are composed of a verb plus a prep and/or a particle. Verb phrases are composed of verbs plus pron/plass+n/a/pron+n/a+n/conj+n/n+v/n+inf,etc./n structure. Phrasal verbs and verb phrases are different from each other, but they share one thing: their meaning are all fixed. Therefore they are idioms.