Fred goes to the doctor's and sits in a chair,

And worringly says,"Doctor I keep seeing fish everywhere !"

Doctor asks,"Have you seen an optician,tell me ?"

Fred  says,"I've told you once it's fish that  I  always see  !"

There's something fishy going on,

To the optician  Fred has now gone,

Hopefully the optician will fish and find out,

How Fred's problem has come  about.