What Am I Riddles

Question: What has teeth but can't bite?

Question: Always old, sometimes new. Never sad, sometimes blue. Never empty, sometimes full. Never pushes, always pulls.

Question: A powerful spell, the naive knows it well; one cast at an affair for your most popular gown. No sticks, no stones, a mage sans tomes, a fight, no toil but it still breaks you down.

Question: My thickness is no more than a few centimeters, yet my depth can span to infinity. Although mundane, I intimidate most animals. When in my presence, you will inevitably follow me. What am I?

Question: I live in water, but not in the same place. Sometimes it’s drinkable and other times it's not. I am either a hunter or gatherer. I am known for being gentle and easy, but I don’t live long. You will know me by my large eyes and goofy lips. People know me by my slimy body. I can be found in your house or out in the wild but never in between. I am friendly so I will likely be your friend in school. What am I?