Good health depends on several things. Fresh air and sunlight are very important for our health. Fresh air helps us to improve our immune system and overall health. So a morning walk is very useful for health. Sunlight helps our body to produce vitamin D. A dirty and damp atmosphere causes lots of diseases. Fresh and pure drinking water is also necessary for good health. Impure drinking- water is the cause of several diseases. So, we must take care of these things.