Problem:

I always wonder about the capability of diversity of our antibodies.

Required:

Question 1: Do we have enough antibodies to fit to every kind of molecule?

Question 2: Wont't it be easier if our antibodies are like clay and can be molded to any form by antigens?

Question 3: Why to waste energy producing so many types of antibodies?

Question 4: If some pathogen makes its antigens just like antibodies of our body, (I think) they won't ever be detected. So what would our body do?

Please provide answers if someone know anout it.