ころ versus とき

[Marshdrifter]

In Beginner Lesson #112, the dialog used ころ in a way that I would've used とき. Is there a difference between the two, and if so, what is it?

Thanks.

[Bueller_007]

In Beginner Lesson #112, the dialog used ころ in a way that I would've used とき. Is there a difference between the two, and if so, what is it?

Thanks.

I'm pretty sure they're both acceptable in this case, but personally, I would go with "koro" here over "toki" just as they did.

The key difference between the two is that "toki" just means "time", so it can refer to an instant in time, or an era of time. "Koro" specifically refers to a long(ish) period of time, so you can't use it in phrases like "when I closed the door". You have to use "toki" (or one of the other numerous Japanese time words) here.

To me it just sounds more natural to use "koro" in #112. I think the use of "toki" is acceptable, but it might be an example of "foreigner's Japanese"--something they teach in introductory textbooks because using "toki" (a word most beginners already know) is easier than using "koro" (perhaps a new word). Grammatically correct, but perhaps not the more natural of the two.

By Google comparison, 子供の時 gets 857,000 hits and 子供の頃 gets 6,620,000.