Using To-Infinitives with Modals
All modal verbs, apart from ought to, require the bare infinitive after it. These modal verbs include: must, can, could, will, should and shall, would, may, might.
- Look at this car! It must be expensive.
- Jake can swim very well.
- My parents will be mad!
- I think you ought be ashamed.
- I think you ought to be ashamed.