
英作文の上達は英語で日記を付けるに限るよ。

I've fixed and adopted it.

Is there a difference between は and には or could both be used here?
Is には needed because 上達 refers to an action?

@JimBreen Example for 〜は〜に限る
I keep forgetting whether you want to be tagged when structure changes are made or if you go through them yourself

>Is there a difference between は and には or could both be used here?
Is には needed because 上達 refers to an action?
I don't know. I just feel には sounds good for that.
風邪を引いたときは、早く寝るに限る。
風邪を引いたときには、早く寝るに限る。
休みの日は家でのんびりするに限る。
休みの日には家でのんびりするに限る。
As you know, には is emphasis. It doesn't always work for that, though.
https://www.edewakaru.com/archives/21647664.html

Thanks. I'd pick up that change through my alerting script.