doesn't
v.v. the short way to say 'does not'. You use it to make a negative sentence when talking about one person or thing.
v. the contracted form of 'does not'. Used as an auxiliary verb to form the negative of the third-person singular in the present simple tense.
He doesn't like coffee.
The new software doesn't work on older computers, so we need to upgrade our hardware.
While the theory sounds plausible in a vacuum, it doesn't account for the socio-economic variables that typically dictate consumer behavior in emerging markets.
From does + -n't.
Used with the base form of the main verb. Functions as the negative auxiliary for third-person singular subjects (he, she, it).
He doesn't likes coffeeHe doesn't like coffeeAfter 'doesn't', the main verb must be in its base form without an 's'.