paraphrasing - Singular vs plural + per + noun?

I would like to paraphrase a sentence:

"This is how the costs of each course should be."

So my idea was:

"This is how the price/prices per course should be."

What are the differences between singular + per vs. plural + per?

Or

If you have better paraphrases, you're very welcome to share them.

Thank you very much :)

Answer

I don't know where you got the original sentence, but it's odd in two ways.

1. 
   

   The "costs" of "each". This implies that each course has more than one cost. This is possible. There may be a cost for full-time students and a different cost for part-time students, etc. But I wonder if the intent was not that each course has one cost. There are many costs, but only one for each course.

   
   


2. 
   
   

   "how the costs should be" Normally we would say "what the costs should be" or "how much the costs should be". "How" indicates a method, like "how to bake a cake" or "how we will find our way out". A cost does not normally have a method. It has an amount. Oh, another possibility is that the writer meant, "how the costs will be determined".

   
   

As to your paraphrase, the most likely wording is, "This is what the price per course should be." Other wordings are possible depending on just what you're trying to say.