I'm learning English with text books, and one of them says tenses of adverbial clauses which means time or condition(such as when-clause or if-clause) depend on the main clauses to which they are subordinate and are interpreted relatively to the tenses of the main clauses, if the main clauses mean something about future.
For example, in the sentence "I will leave before he comes.", "come" is used in present tense even though "he comes" means something about future and not about present. For another example, in the sentence "If it rains tomorrow, the match will be canceled.", "rain" is used in present tense depending on the main clause "the match will be canceled" meaning something about future even though the meaning of "rain" is about future here.
If what my text book says is right and tenses of adverbial clauses which means time or condition depend on the main clauses to which they are subordinate and are interpreted relatively to the main clauses, the following sentences would be right, and I would like to know they are right or not.
"I will go abroad after he graduated." meaning that "graduated" is about the past in relation to the future the main clause means and it is actually about the future.
"John said that his daughter would leave before he comes." meaning "comes" is about the present in relation to the future which "his daughter would" means in relation to the past which "John said" means.
What I would like to know is whether tenses of adverbial sentences in these conditions are used and interpreted relatively to the main clauses to which they are subordinated or not.
Thank you very much for reading such long sentences so far. My explanation might be not so good and it might be difficult to understand well what I would like to know. But it's very thankful if I could hear some opinions.