English, like other languages, has “modal verbs”, which express the relationship between a speaker and an action like obligation, desire, ability and so forth. They include can, should, must, dare and the like. These verbs take an infinitive after them: can go, should work, must sleep, dare try. If you’ve heard that an infinitive must have to before it, you will wonder if these are really infinitives, but they certainly are – a “bare infinitive” is one that has no to before it. Modals take bare infinitives.
