Multi word verb

Multi-word verbs are verbs that consist of more than one word, e.g. had better, used to, be going to, ought to. Although they can be synonymous with phrasal verbs, in the strict sense there is a distinction between the two, where multi-word verbs is a term that covers both phrasal verbs (verbs + adverbs) and prepositional verbs (verbs + prepositions). They are used as modals, but they are semi-modal rather than modal verbs. This is an example of periphrasis.