Shyness (害羞) means feeling afraid when you're around other people. Some (child) are born shy. Some become shy later because of (they) life experiences. In fact, everybody (get) a little shy sometimes.
Most people have red faces and can talk in broken sentences they are shy. But some become so shy that they won't go to a restaurant because they are too nervous (order) their food. Some are afraid meeting new people, so they (hard) go outside. This kind of shyness can be bad for a person.
You are shy but you can still do something you want to do. Some shy people do better in (finish) work than others because shy people think(much) but talk less.
But remember not to let good chances go just because of shyness. If you have a chance to sing a song atbirthday party, just do it. There is nothing to be afraid of.