Another big error is to use the apostrophe to indicate more than one person in a family: "The Burke's are having a great party tonight." NOPE. Let's try it this way: "The Burkes are having a great party tonight." or if you insist on using the apostrophe: "Let's go to Mr. and Mrs. Burke's party tonight!" BTW, I need a good party!
Please don't consider these criticisms, but lessons from a perfectionist. In the long run, some simple rules will make you look really smart! Your feedback and more examples are appreciated. I especially have fun with signs, so if you see any good ones, I'll post the pictures!