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If we have several items to mention, which should be separated with or, is this correct to use the for each one? Could it be possible to use one "the" to distribute among them?
For example, which of the following questions is proper?
When we teach this unit, should we focus on the textbook or the presentation?
When we teach this unit, should we focus on the textbook or presentation?
This question differs from the question put in the topic: Is it necessary to use "the" multiple times?, since the separation by the conjunction or has not been addressed in this topic.