I am somewhat brown skinned though my skin colour is in chest area and my upper arm. But around my knee and elbows my skin is totally black... as though clogged up with dirt.

How do I make my skin colour near my knee normal again? And why does my chest and upper arm have a much lighter colour than the rest of my body?

Please reply
Thanks!

The skin differs on different areas of the body. The skin on the elbows and knees is much thicker and dirt can penetrate those areas. Use a facial scrub two or three times a week to exfoliate the dead skin and dirt from your elbows and knees. You may also want to use a hydroxy cream or a bleaching cream to help fade the discoloration.

Clean your elbows a lot more - filthy monk.