遮 versus 捂 versus 盖 in terms of usage
捂: cover small things almost entirely by a hand or hands
遮: cover large things partially or entirely by things like a sheet or a piece of paper
盖: cover something entirely by things like a lid or a cap
捂住耳朵 is better than 遮住耳朵 or 盖住耳朵 obviously.The latter two are also acceptable and understandable.cover up a situation: 掩盖/遮盖/遮掩/隐藏事实/事情, 掩盖 is the most frequently used word.