问题详情：
The idea of giving blood is very simple, that idea has saved many thousands of lives over the past century.
Doctors have been carrying out blood transfusions for hundreds of years. ___41___.起初,他们从绵羊身上抽血. But that wasn’t very successful. It wasn’t until last century that doctors realized there are several types of blood. ___42___. and that the correct type must always be used. Once they knew that, blood transfusions had become almost 100% successful.
So, you might be thinking, what does this have to do with me? Well, ___43___.它与我们大家都有关系. Hospitals need to keep banks of blood ready for transfusions. The only way they can get that blood is from ordinary people like you. ___44___. Every human body about 5 liters of blood, and we take 0.5 liters from each person. This is completely safe. In fact. ___45___. your body will make enough blood to replace it in a day. It costs you nothing, and it could save a life. So please give blood.
【回答】
41. At first, they look blood from sheep
42. 而且必须总是用正确（相匹配）的血型
43. it has something to do with all of us
44. 每个人体内有5公升的血液
45. 在一天里你的身体会再造足够的血液来替代
知识点：翻译
题型：未分类
