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     Is human blood all the same? "Yes." You may say. "It's all red." 

     Well, it's not as simple as you might think.

     Blood is made up of different parts, such as red blood cells (红血球), white blood cells and platelets

(血小板).

     Two chemical molecules (分子) on the red blood cells make people's blood different. Scientists mark one

molecule "A" and the other molecule "B". According to which and how many molecules are on the red cell,

scientists divide blood into four types: A, B, AB and O.

     Your blood type will stay the same all your life.

     Scientists have been wondering if there are some links (联系) between people's blood types and their

personalities, but they are not certain.

     But some say that people with the same blood type may have things in common.

     What's your blood type? Do you have family members or friends who are of the same type as you? Read

the following.

     People with Type A: They look peaceful from the outside. But they ask too much of themselves that they

may be very nervous inside. They get happy or sad easily. Sometimes they are shy but always very careful.

They can easily win people's trust.

     People with Type B: They have strong minds. Once they start a task, they don't give up easily. They'll try

their best to finish it and do it well. Type B people always try to make themselves different from others. They

want to do things in their own way.

     People with Type AB: They are maybe the strangest among all blood types. They can be both open and shy,

noisy and quiet at the same time! They are responsible and always ready to help others.

     People with Type O: They are open and good at making friends. They always start tasks but don't always

finish them. They have lots of new ideas and love to be the centre of attention. They always strongly believe in

themselves.

1. The blood types are decided by _______. [ ]

A. the kind and amount (数量) of molecules on the white cell

B. the kind and amount of molecules on the red cell

C. the kind and the amount of platelets

D. the amount of white blood cells

2. Scientists are _______ about the relations between blood and personalities. [ ]

A. sure

B. not sure

C. worried

D. excited

3. If you are with Type B, you might _______. [ ]

A. have strong minds

B. be always ready to help others

C. look peaceful outside

D. always start a task and don't finish it

4. If a person is both open and shy, noisy and quiet at the same time, he or she might be with _______ blood. [ ]

A. Type O

B. Type A

C. Type B

D. Type AB

5. The best title of the passage is _______. [ ]

A. Blood Type

B. Red Cells and White Cells

C. Personality

D. Blood Type and Personalities