Good Riddles

Question: What goes back and forth constantly, but never in a straight line?

Question: If you have two twins, three triplets and four quadruplets; how many people do you have?

Question: What goes round the house and in the house but never touches the house?

Question: There were five men going to church and it started to rain. The four that ran got wet and the one that stood still stayed dry. Which one stayed dry?

Question: Although I'm far from the point, I'm not a mistake.
I fix yours.

What am I?