grammar - Can a noun + suru have an adjective modify the noun as well?

”I did some difficult studying last night."

Could I say, "昨夜、難しい勉強しました。”?

Basically, my question is: can an adjective, relative clause, or adjectival phrase modify a noun that has する attached, for example 勉強をする or 勉強する?　And does it make that word or phrase actually adverbial when applied like that?

Answer

(The combination 難しい勉強 sounds slightly off to me, but I put this aside for the purpose of this question.)

You have to distinguish noun+する and noun+をする.

• Noun+する: Once you attach する, what was originally a noun becomes a verb, and you cannot modify it with an adjective.


• Noun+をする: Attaching をする does not change a noun to a verb, and you can still modify it with an adjective.

For example, 難しい勉強する is ungrammatical (although this is not unheard of), whereas 難しい勉強をする is grammatical.