The semi-modal DARE

Dare means "have the courage to do something" and can behave either as a modal verb or as a main verb:

• As a modal verb, dare is used in negative and interrogative sentences; it is followed by a bare infinitive:
  

  I daren't think how many victims there are.
  How dare she criticise us?

• Dare as a main verb can be followed by a bare infinitive or a to-infinitive:
  

  Do you dare (to) tell him what happened to his bike?
  Who dares (to) argue with me?
  He didn't dare (to) look back.
  No one would have dared (to) think about it.

  But in the expression Don't you dare..., it is always followed by a bare infinitive:

  Don't you dare interrupt me!