Why "doesn't"?  Why not "dusn't"?

doesn't の oe は、/ʌ/の おとで よむ。これは ふきそくな よみかたで ある。


よみかたが わかる ように つづりを かきなおす。


doesn't --- dusn't


えいご では、/ʌ/の おとは u で かくのが いちばん きそくてきで ある。



It dusn't matter.


It dusn't matter to me what you say.


It dusn't anser my question.


most peeple make lots of mistakes and it dusn't matter.


Too much meat dusn't agree with me.


This cake dusn't agree with my taste.


He dusn't watch television at all.


Crime dusn't pay.


Perseverance dusn't always pay off.


The restaurant dusn't do lunch.


Money dusn't grow on trees.


My memory dusn't go that far.


She dusn't hav a good memory.


She dusn't hav much knolledge of French.


She dusn't seem to think that way.


She dusn't smoke much these days.


She simply dusn't want to.


If it dusn't help you, why do you keep doing it?


Why dusn't my password work?


Why dusn't my site show up at all when serched?

Blocking access to child porn dusn't help victims, expert says


Nobel Peace Prize Dusn't Help Obama