【正文】
people who do the cleaning D people who will live with a family 47 Which of the following is not talked about in the rules?A The name of the host B The time to go to bed\C Something you can’t do D The address you will be staying at 48 You can do the following except ________________.A taking showers at 9 . B smoking out of the bedroomC telling the host at 7 . if you don’t have dinnerD using the host’s mobile phone to receive phone calls 49. When you are out, you must __________________________.A take showers B have dinner C make calls D clean the room 50. If it is ., you can do the following except _________________.A have dinner B take showers C go to bed D stay outCWhen you cut your skin, you bleed(流血). If a person loses a lot of blood, he will bee ill and may die. Blood is very important. People have always known that. At one time, some people even drank blood to make them strong!When doctors understand how blood goes around inside the body, they try ways of giving blood to people who need it. They take blood from the healthy people and give it to people who need it. This is called “blood transfusion”. The blood goes from the arm of the healthy person into the arm of the sick person.But there are two problems. First, it does not always work. Sometimes people die when they have blood transfusion. Later, doctors find that we do not all have the same kind of blood. There are four groups—O, A, B and AB. We all have blood of one of these groups. They also find that they can give any kind of blood to people of group AB. But they find that they must give Agroup blood to Agroup blood people and Bgroup blood to Bgroup blood people. I have Ogroup blood and the doctor told me that I could give blood to anyone else safely.There is another problem. To give blood of the right kind, doctors have to find a person of the right blood group. Often they can not find a person in time. If they have a way to keep the blood until someone needs it, they can always have the right kind of blood. At first they find they can keep it in bottles for fifteen to twenty days. They do this by making it very cold. Then they find how to keep it longer. In the end they find a way of keeping blood for a very long time.We call a place where we keep money a“bank”. We call a place where we keep blood a “blood bank” One day, when you grow up, you may decide to give blood to a“blood bank”. In this way you may stop someone from dying. Or perhaps one day you may bee ill. You may need blood. The“blood bank”will give it to you.51.From the passage, we learn that sometimes people die when they have blood transfusions because they .A.a(chǎn)re unhealthy people B.have lost a lot of bloodC.a(chǎn)re not given the right kind of blood D.a(chǎn)re ABgroup blood people52.Which of the following is true?A.Doctors can give any kind of blood to the writerB.The writer can give blood to Bgroup blood peopleC.The writer has never had a blood transfusionD.The writer has the same kind of blood as his father53.People set up the“blood bank”so that they can .A.give the right kind of blood to the people who need it in timeB.keep different groups of blood as much as possibleC.make it easier to sell or buy bloodD.keep blood for more than twenty hundred years54.From the last paragraph(段落)of the passage, we learn that .A.the writer thinks it’s good to give blood to a “blood bank”B.we may bee ill if we give blood to a “blood bank”C.many people died because they lost a lot of bloodD.blood is more important than money55.Which is the best title of the passage?A The Importance of Blood B Four Groups of Blood C Blood Transfu