Commonly used mercury thermometers should be used to measure body temperature by keeping the mercury column below 35°C, avoiding activities that change the temperature, the time of measurement, and the method of measurement. Try to choose a mercury thermometer and keep the mercury column below 35℃. Do not consume diets that are too hot or too cold, such as boiled water and ice cream, before taking the temperature, and avoid sports activities that can raise the body temperature. If you find sweat in your armpits before measurement, dry them before taking the temperature. Before the measurement, pay attention to keep in mind the time, the time is not less than 5 minutes, the general measurement time is 5~10 minutes. If the thermometer suddenly slips or comes loose, repeat the measurement. Remove the thermometer and take a reading. Shake the thermometer mercury column to 35℃ and sterilize it for storage. Do not clean the thermometer in hot water.