It was nice to hear from you. Let me answer your questions.
People who use portable music players are less aware of their surroundings because they are focusing on listening to the music. As a result, they may bump into people or could possibly cause serious accidents.
As for bike helmets, head injuries are common even in minor accidents, so helmets can save people's lives. Therefore, all cyclists in Japan should be made to wear them.
I think it is great that you can learn first aid at school. Accidents in the home are common, so it is important that people know how to deal with emergency situations.
