Ok, this has been bugging me long enough. In the sentence " I drove my car to joes house. " where exactly in the word joes does the apostrophy go? Every time I see a word like that the apostrophy is before the S no matter what context they are using the word. Last I knew, the apostrophy was there to take the place of a letter. So instead of joe is, one would write Joe's. But if I wanted to use my example setence, wouldn't the apostrophy go after the S?
Ethel is right. Apostrophes are used to show possession or if two words are shortened, e.g. it is - it's, they are - they're. The car belongs to Alan - Alan's car, the car belongs to the Smiths - the Smiths' car.