Will having less than one drink impair your driving?

Not unless it was a really big drink. One standard drink (equal to about 1/2 oz. of alcohol) will not raise your blood alcohol sufficiently to pose a problem.
No.

But it can screw up you grammer. It can cause you to add extra Words to questions that are not needed. So please, stop drinking, your grammer is terrible.

firstly lol^ and-Side note the right amount of alcohol can actually imporve your reflexes and reaction times (in short the right quantity makes you better) HOWEVER this quantity is rather small and in most people much less that a standard drink (if you can fell the effects i.e tipsy you have had to much, and if you have had 2 standard drinks or more you have had way to much to recive this effect(well you'll recive the effect when you start to drink for a brief moment then it's all down hill from there.))

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