tense with after

[aflaamM589]

Hello Experts,

On thursday morning, five minutes after the class had begun, two policeman entered the classroom and arrested the teacher
vs
On thursday morning, five minutes after the class began, two policeman entered the classroom and arrested the teacher

Is the second version prefered to first because after makes the time sequence clear?

Thanks

[RonPurewal]

the first one is wrong. the second one is right.

think about it like this:

if bobby graduates from college, then, "bobby has graduated from college" is something that is true FOREVER from that point onward.
therefore, there's no such thing as "...AFTER bobby has graduated", because "bobby has graduated" never STOPS being true.

on the other hand, "after bobby graduates" (or "after bobby graduated", if it's in the past) makes perfect sense.