いつ and とき how to tell when to use which My book has one example of the use of the second one; , which essentially is asking when you were in high school were you a good student though i am confused why instead of but that is a whole nother problem. I doubt its as simple as one is a current tense and one is a past tense when. perhaps one is the question when and the other is a time when? I have no idea what to tag this please fix for me.

You're on the right track. is an interrogative, a question word. It's used to ask when something happened or will happen, not to talk about a particular time period. In English, we say:

> _When_ I was in high school.

In Japanese, it's:

> __

(There's nothing wrong with saying ; it's just a little less common, probably because it's an extra word. In English, you can say, "Back in high school" or "When I was in high school" or "When I was a high school student...")

and are never interchangeable. For example, you can say:

>

When is the class? If you replaced with , the sentence would make no sense.