So I'm working on some exercises in the volume I Genki textbook and I came across a question that asked me to make a sentence to say that I think Mary often cooks.
So I had: メアリさんはよく料理すると思います。
As the textbook lists to cook as 料理する。 But the answer key gave:
メアリさんはよく料理をすると思います。
I don't quite understand why the answer key gave the answer it did. To the best of my knowledge both sentences translate to "I think Mary often cooks". Is the second one more natural in Japanese than the first? And if so does the same apply to all noun + する verbs when they're preceded by a quantifier?