We often see blood donation（献血）buses on the road. As we all know, blood is very important in medical activities. However, some people are afraid of donating blood. Actually, it can not only help others, but also do good to your body.
Firstly, people who are too thin cannot donate blood. If you are underweight, you may become very weak after donating blood.
Because blood donation may make you feel worse, and the virus（病毒）in your body may spread through blood.
Thirdly, people between 18 and 55 years old are at their best ages to donate blood.
Finally, close relatives should not donate blood to each other. This is to prevent（预防）TA-GVHD, an illness that can be very dangerous to the person who receives the blood.
If the answer is "Yes", be sure to remember the rules!
A. Sleeping late often is bad for your blood pressure.
B. Here are some facts you should know about blood donation.
C. Will you choose to donate blood when you become an adult?
D. Secondly, you can't donate blood if you have a bad cold or the flu.
E. Because the health of underage and elderly people is taken seriously.
F. Blood donation among close relatives can lead to a very serious illness.
G. The weight of men should be over 50 kg, and the weight of women should be over 45 kg.
