We went to playland today. All the things there are too exciting for me.It reminded me of the article about zero-gravity roller coaster. In my opinion, that is unsafe, everyone having desire to try it should accept a physical test, but most of parks just have the warning notices in front of the entertainment facilities . Furthermore, many people don't know their physical condition when they take the exciting facility, so it  must be a problem. Also friends sometimes can do help to create the impulsion, but not everyone is suitable for joining risky things.