Well, don't is used when the subject is in present tense, and wasn't used in past tense.
no you didnt
we dont know
i am Appalled at how you dont know the answer
i dont knoe hahahahhahahah
i dont know can you
you dont know it dummy
i sliced a apple in two but i dont know how to use bisect in a sentence
You just did but, " It is very uncommon that he didnt go to work today."
I Dont freakin NO =)
i dont know the answer
i dont want to complicate things
Dont disrepair the bicycle.