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I understand how 時 works with plain present/plain past (e.g. 食べる/食べた時) but I'm a little unsure of ている/ていた時.
Also what's the difference between these two sentences:
In a textbook apparently they both translate as "When I was taking a bath, the telephone rang." But I don't understand why.
If someone could please explain this for me I'd really appreciate it! (I hope it's not too broad a question.)