We use vinegar, an acid, to pickle cucumbers. Acids like these are help us. But, acids can also be harmful. If there is too much acid in garden soil, plants will not grow. Some acids will burn your skin.
Acid rain is harmful rain.
Leaves burned by acid rain cannot make oxygen or collect carbon dioxide needed for photosynthesis . We cannot create new water. For millions of years, the water we have has been used again and again. We have been able to do this because there are natural cycles that clean the water each time we use it. People are causing our water to be polluted.