Questions & Answers about Да, я ездил в Азию, когда был студентом.
Why use the imperfective verb ездил here instead of a perfective verb of motion?
This is the general factual use of the imperfective aspect. The speaker is simply confirming the fact that the trip happened as a life experience, rather than focusing on a specific completed result. For verbs of motion, the multidirectional past tense like ездил is the standard way to express that you went somewhere and came back.
Could I use ходил instead of ездил if I just mean that I went somewhere?
No, because Asia is a continent, which implies long-distance travel. The verb ходил is for traveling on foot or moving locally, whereas ездил specifically means travel by some form of vehicle. When talking about international trips, you must use a riding verb like ездил.
Why is студентом in the instrumental case?
When stating who or what someone was in the past using был, Russian typically uses the instrumental case for temporary states, professions, or phases of life. Using the nominative case here would sound less natural, because the instrumental specifically highlights that being a student was a temporary period that has now ended.
Why do we use the accusative в Азию instead of the prepositional в Азии?