2、A person has been badly injured in a car accident. It is necessary to give him a blood transfusion because he has lost a great deal of blood in the accident. However, special care must be taken in selecting new blood for him. If the blood is too different from his own, the transfusion could kill him.

There are four basic types of blood: A, B, AB and O. A single test can tell us a person’s blood type. Everybody is born with one of these four types of blood. Blood type, like hair color and height, is inherited from parents. Because of the substances contained in each type, the four groups must be transfused carefully. Basically, A and B cannot be mixed. A and B cannot receive AB, but AB may receive A or B. O can give to any other group; so it is often called the universal donor. For the opposite reason, AB is sometimes called the universal recipient(领受者). However, because there can be so many reactions in transfusions, patients usually receive only salt or plasma (血浆) until their blood can be matched as exactly as possible in the blood bank of the hospital. In this way, it is possible to avoid any bad reactions to the transfusion.

There is a relationship between your blood type and your nationality. Among the Europeans, about 42 percent have type A while 45 percent have type O. The rarest is type AB. Other races have different percentage. For example, some American Indian groups have nearly 100 percent type O.

1、When I was about twelve, I suddenly developed a great passion for writing poetry. I gave up all my other  21  , such as playing computer games,   22  foreign coins and stamps, and spent all my spare time reading poetry and writing it. This habit of writing poetry on every possible  23 

soon got me into trouble at school. If a lesson did not interest me, I would take out my note-book and start writing poems in class. Of course, I did this very  24   , but it was not long before I got

  25  . One day while I was busy writing a poem during a geography lesson, I looked up to find the teacher standing over me, staring with anger because I was not   26  attention. He tore the paper up, with a   27  not to waste time in his lesson. All the same I was convinced that I had written a good poem, so that evening I wrote it out again from memory. Not long after, I read about a poetry contest and I decided to send in my poem. Weeks later, long after I had given up hope, I got a letter informing me I had won first   28  . Everyone at school was very impressed ―except the geography teacher, who    29  me more carefully than ever. He was quite    30   that I was going to write poetry in his lesson!

27、

I don’t think ___ is any need for a guide on our journey.

A. it        B. this            C. that            D. there

26、 It is very late and it has started to rain, so he ___ it ___ whether she will come as she promised.

A. felt; unsure        B. feel; unlikely            C. feels; uncertain         D. felt; unnecessary

25、 If it ____ for the snow, we ____ the mountain yesterday.

A. were not; could have climbed                 B. were not; could climb

C. had not been; could have climbed           D. had not been; could climb

24、 --Is Blake still absent from class?

--I think he        be punished if he goes on with it.

A. shall          B. must          C. can            D. will

23、 The new books are of great use. They  ____ well and ____ already.

A. sell;  sell out                           B. sold; had sold out

C. sold; have sold out                  D. sell; have been sold out

22、They have ____ that any faulty parts will be replaced free of charge.

A. allowed                    B. guaranteed         C. ensured             D. protected

21、____ seen the film, so everyone wants to see it.

A. All the students haven’t           B. Any student hasn’t

C. None of us has                        D. As anybody has

20、I send you 100 dollars today, the rest_____ in a year.

A. to follow           B. followed           C. follows             D. being followed