it is unavoidable that man gets ill sometimes.it may be owing to some epidemic virus or the disorder in your body adjustment or simply the decrease in immunity.take cold for example,when you catch a cold ,you are likely to have a sore throat,a running nose,a cough,a headache or even a fever.so how to prevent from having a cold?there are several ways,such as,take exercises often,this is the most efficient way to keep cold away;drink enough water and don't stay up late;put on and take off clothes according to the change of the weather.