Where can also be used after some specific nouns such as situation, point and stage, e.g.:
Eventually I reached a stage where I began to enjoy my work.
He found himself in a situation where he was unable to pay off his debts.
When can be used as a relative adverb in a relative clause after the word time or other nouns which denote periods of time such as year, day, summer, etc.
I remember the day when I first met her.
Wasn’t that the summer when we took the boys camping?
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