Can somebody explain when to use "explanation for" or "explanation of"?
Native speakers of English seem to differentiate "explanation for" and "explanation of". But when should I choose one over the other?

Question

Can somebody explain when to use "explanation for" or "explanation of"?
Native speakers of English seem to differentiate "explanation for" and "explanation of". But when should I choose    one over the other?

Answer

explanation for something = a reason something occurred
explanation of something = a description of something

Explanation for your bad grades = "I didn't get much sleep", "I didn't study", "the teacher is very intimidating"
Explanation of your bad grades = "I got a D in math", "I failed my oral exam", "I received an incomplete on my homework assignments"

Answer

"There can be no explanation for this bad behaviour"
"Can you give me an explanation of the different uses of this word?"

In the first case, there is no explanation why something happened.
In the second case, "of" is used normally.

If I think of a better way to explain myself, I'll post a comment later, but I hope this gives you a start.