Good Riddles

Question: When you're given one, you'll have either two or none?

Question: What word begins with letter H, but add it with W and it becomes another word yet pronounced just the same?

Question: What falls but never breaks, and breaks but never falls?

Question: It's a question you can ask all day long and get completely different answers although these answers could be correct. What question is it?

Question: There are five fish in a fish tank. Two swim away, one swims towards the ocean, and two die. How many fish are left in the tank?