Re: the plane "arrived" or "has arrived" an hour ago
It's nothing to do with arrivals and departures; it is to do with how we locate the action in time. The following are all correct:
Originally Posted by azhu
The train has left, so we'll have to catch the next one.
The train left an hour ago.
The train had left by the time John got to the station.
Our train was leaving as we got to the platform.
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