In the following sentence, should I use "explanation" or "explanations"?
I needed to tailor explanation(s) to each student.
I commented on whether the explanations were clear enough.
Well, according to the dictionary, explanation can be countable and uncountable.
Whether it is countable or uncountable depends on your own opinion and the context.
To express a general idea, i.e. uncountable, use explanation without "s".
To express an individuated explanation, i.e. countable, use explanations.