What is ear drum?write down it's function.​

Your dog can sniff at or even eat a bit of catnip. the herb is edible and not harmful. just don't expect them to roll around like a cat would! your dog may scrutinize catnip by licking and smelling at it, or be totally indifferent to this stimulant.

Well, l think that some effective communication is, emotional barriers and lack of attention, interest distraction or irrelevance. also some physical disabilities such as hearing problems or speech difficulties.      l hope i am correct  and you good luck.