一束太阳光通过三棱镜折射后，被分解成七种颜色的光，在白色光屏上形成一条 * * 光带，如图所示，这个现象叫光的_________，最早通过实验研究这一现象的是英国物理学家_________．如果将白色光屏换成红色光屏，我们将_________（能/不能）看到 * * 光带．
色散；牛顿；不能
题目分析：太阳光是复色光，当太阳光经过三棱镜后，会分解成红、橙、黄、绿、蓝、靛、紫七种单色光，这是光的色散现象；英国物理学家牛顿首先研究了这一光的色散现象．不透明物体的颜色由它反射的色光决定，反射什么颜色的色光，物体就呈什么颜色；透明物体的颜色由它通过的色光决定，能通过什么颜色的光，物体就呈什么颜色．如果将白色光屏换成红色光屏，红色光屏只反射红光，我们只能看到红光，故不能看到 * * 光带．
| 阅读短文，选择正确答案。 | |
| RECENTLY hand-foot-mouth disease has spread across China. In the past three months, there have been about 41,846 cases (病例) in 30 provinces and regions. The number is increasing. Eighteen Chinese children have died of the disease so far this year. What causes the disease and why is it dangerous? Hand-foot-mouth disease is a common childhood illness. It mainly affects children under the age of 10. It gets its name from the rash (疹子) that develops on the hands and feet. It can also cause blisters (水泡) in your mouth. A child who has the disease will usually have a fever, a runny nose and sore throat. He or she doesn't want to eat or drink because of pain in the mouth. Hand-foot-mouth disease is mostly not serious. The fever and rash clear within a few days. But in some cases, the virus (病毒) affects the heart, lungs or brain. This puts the child's life in danger. A virus causes hand-foot-mouth disease. The disease spreads easily where a lot of young children are together, such as in a child-care center. Sometimes it can also affect teenagers and adults. In order not to pass on the virus, good hygiene (卫生) is important. We should wash our hands as often as possible. Especially we should wash our hands before meals and after going to the toilet. | |
| 1. More than ______ people have caught hand-food-mouth disease this year. | |
[ ] | |
| A. thirty thousand B. forty thousand C. four million | |
| 2. Hand-foot-mouth disease ______. | |
[ ] | |
| A. is a kind of cancer B. isn't dangerous at all C. can cause death | |
| 3. A patient of hand-foot-mouth may ______. | |
[ ] | |
| A. eat more B. have blisters in the mouth C. have rash on the face | |
| 4. From the passage, we know that the hand-foot-mouth disease ______. | |
[ ] | |
| A. spreads easily among the young children B. will not affect adults C. didn't happen in China | |
| 5. ______ can help us to keep away from the hand-foot-mouth disease. | |
[ ] | |
| A. Passing on the virus B. Taking children to the child-care center C. Keeping your hands clean |