When you feel tired in class, there are many reasons, including The first reason is a lack of sleep; if you don't get enough sleep, you will feel tired and sleepy in class. The second reason is your diet: we always eat high-protein foods, such as fast food, and high-sugar products, which cause fluctuations in your body, make you sleepy and make it difficult to stay awake. The 3 reason is inaction (sitting), all the time you do not get activeness in your body, which causes you to feel tired. Medical conditions: Certain medical conditions, such as sleep apnea, narcolepsy, or anemia, can cause excessive fatigue and make it difficult to stay awake. The fourth reason is a medical condition; many people nowadays suffer from sleepiness disorders such as sleep apnea and norcolepsy. 

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