阅读理解。 What is blood? Blood is a thick, red fluid which carries oxygen, water and food to all parts of the body. It keeps the body at the right temperature (温度) and protects it from disease. If you lose a lot of blood, you need new blood. You can receive new blood from other people. This is called a blood transfusion (输送). People can donate (捐献) blood at a Red Cross Blood Bank. People who give blood are called blood donors (捐献者). Some people sell their blood but many others donate it. Donating blood doesn’t hurt you and it doesn’t take long. First a nurse take a drop of blood from your finger and tests it. She does this to make sure that your blood is healthy. Then you lie down on a bed and another nurse checks your blood pressu re (血压). After that the nurse puts a needl e into a vein in your arm. The needle is attached to a tube. The blood flows through the tube into a plastic bag. After about 10 minutes, when the bag is full, the nurse takes the needle out of your arm. You stay on the bed and rest for a few minutes. Finally you go into another room and have something to ea t. For a healthy person, donating blood i s not harmful or painful. Bu t the blood he or she donates may save someone's life. 1. Where can people go to donate blood? ________________________________ 2. Why does the nurse first take a drop of blood from the finger? ________________________________ 3. What do you do after the nurse takes the needle out of your arm? ________________________________ 4. Do you think you need something to drink after donating blood? ________________________________ 5. Is donating blood harmful for healthy people according to the passage? ________________________________