You may get a cold sometimes. It often starts with a sore throat. You sneeze (打喷嚏) and your nose runs. You usually have a headache, too. Often you have a cough later. It's not a serious illness, but you may feel quite bad.
 There isn't a cure (治愈方法) for the cold, but you can take some medicine to make you feel better. For example, you can take aspirin (阿司匹林) to get rid of (摆脱) your headache. It is good to rest and drink a lot of water, too. A doctor once told me, "With the right medicine, the cold will last for seven days. With no medicine, it will go on for a week!"
Where does our medicine come from? A long time ago, people knew that some plants made them feel better. For example, the juice of lemons (柠檬) makes a sore throat better. Now, scientists find some parts of plants can make some medicine. Because of these medicines, people now live longer than their grandparents.