我第一次献血时20岁。
Most people are able to donate blood again in several months if they wish.如果他们愿意,大多数人可以在几个月内再次献血。
Some people think it is a good thing to donate blood for it could save somebody's life while others insist that we should not donate blood for it may cause some illnesses.有些人认为献血是一件好事,因为它可以挽救某人的生命,而其他人坚持认为我们不应该献血,因为这可能会导致一些疾病。