This is why writing is important. it gives you the time to actually thinking about the best words to represent what is in your head. you may still fail, but it will usually be better than whatever comes dribbling out of your mouth.

unfortunately, if knowledge isnt written down in some form, (code, english etc) then it doesnt really exist in a civilization sense, so you need to get good at writing.

see all Paul Grahams essays on writing.