Mark Twain said something like "Say nothing and they'll just wonder if you're a fool. Open your mouth and you'll remove all doubt." If he were living today, he would certainly not aim that remark at you, because you're reading the GrammarPhile blog and that makes you smarter than the average bear (we hope!). You always want to appear intelligent, don't you? Study these words and use them properly. Mark Twain would be proud of you.