In the centuries after the group separated, they evolved in opposite directions.
Shouldn't the former part of the sentence be in past perfect and 'had separated' be used instead of just 'separated'?
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Sign up to join this communityIn the centuries after the group separated, they evolved in opposite directions.
Shouldn't the former part of the sentence be in past perfect and 'had separated' be used instead of just 'separated'?
In English both “separated” and “had separated” are in use and acceptable. This is in contrast to some other languages with more prescriptive rules about the succession of tenses.
Other things being equal, I, like the poster, would prefer the past perfect to follow the perfect and would regard the use of the perfect as rather lazy.
However other things are not always equal, and there are cases where one or the other is — in my opinion — more appropriate. Consider the following pair of sentences:
In the first example the adverbial phrase refers to the immediate events following the separation (in this case, presumably temporary). In the second case the adverbial phrase covers a longer period of time following the separation (in this case, presumably permanent).
However this is only my preference, and contrary usage is common.
In the centuries after the group separated, they evolved in opposite directions.
The business in front of the comma is an introductory adverbial phrase relating to time. They normally have the same tense as the main clause.
When the focus is on the current event:
Past Mixed Time Frames
Contrasting earlier and later past eventsThe timing of two related past activities is expressed with past tense verbs in both the main clause and the clause that complements (completes, follows) the preposition—after, before, when, while, etc.
Optionally, the adverbial phrase may employ a past perfect when emphasizing the time relationship of past events. When the focus is on the earlier-later timing of the events:
A contrast in the timing of the two events may be expressed with a past tense verb in the main clause and a past perfect verb in the clause that complements after, before, when, while, etc. Past perfect is optionally used to emphasize or make clear the difference in timing.