Nancy Johnston, one of the therapists at the clinic where I work, was chatting with a little boy as they made pizza in our clinic kitchen area.
   
Do you want to little cheese on yours or a lot?  She asked.

The predictable answer was immediate. A lot.

You want a lot of cheese, she said, so you must be kind of a cheese guy. 

No, her young friend answered, I am a boy.
 
Nancy began to explain that if you like something a lot, for example, trains, then you could say "you are a train guy."  She reminded him of how much he liked trains.  He looked baffled.
 
I was in the same kitchen area, warming up my lunch and I decided to help out. 

I am a bicycle girl.  I said.  I pointed out into our play yard where my bike was parked.  I ride bikes and I like them so people can say that I am a bike girl.

I was a little worried that the wording "bike girl" versus "bike guy" might be confusing things as soon as I finished talking.  Nancy was seeing the look of confusion, still clearly on her young friend's face too.  She turned to the little boy's dad and asked him what he likes.   

I like books dad said.

Your dad is a book guy, Nancy proclaimed.

We were using a teaching strategy that seems obvious but it is worth explaining.  Our strategy for teaching this new phrase was to use the same exact phrase over and over, with lots of examples of how the phrase could be used. We tried to use examples that the child could related to.  If people make a mistake in using this strategy it is in thinking that one explanation will be enough.  The other mistake is that they don't use the exact same language over and over.  I was worried that by changing even one word, I might have confused things--and I might have.  This little boy's dad did not quite understand what we were doing or maybe he did but just got distracted from the mission that Nancy and I were clearly on as we tried to explain why one would call a person who likes cheese a "Cheese guy."  Anyway, Dad said:

I like books so I am a book worm. 

I thought his son was going to fall off his chair as he laughed and laughed.  I don't think dad's example helped to clarify the concept but it gave us all a great laugh as we saw, through a child's perspective, what a funny language we speak.