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I have a question about the word when. I have read that it can be a conjunction or a relative adverb (either way, it joins two clauses together). Can I ask how do I differentiate between the two?
A few sample sentences are:
1) He graduated from school when he was 22 years old.
2) The risk of theft is higher when you do not install a car alarm system.
3) I remember the day when we first met.