1. BENEFICIAL : producing a favorable result.
2. DERMATOLOGICAL : having to do branch of medicine concerned with the skin.
3. OSTEOARTHRITIC : having a degenerative bone disease.
4. PATHOLOGICAL : relating to or caused by disease.
5. CREDENTIAL : that which entitles one to confidence, credit, or authority.
6. POLYTHEISTIC : pertaining to the belief in more than one God.
When talking about recycling, people don't seem to consider the recycling of clothing.
The comma should be placed between the first use of recycling and people. The subordinate clause is "when talking about recycling". This is a clause because of the word "when". When makes the reader wonder when what? The main clause is "people don't seem to consider the recycling of clothing."