Sentence Correction (SC) | Re: Archeologists speculated for decades about why the Anasazi

fmik7894 arvind910619

I am no expert, but let me add my two cents.

We definitely needhave speculated (present perfect) since the archaeologists had speculated in past
and are still speculating. It isnot a point of time event (speculated, ie simple past tense) that happened in past.

Alsoappears (simple present - suggesting a fact) to have been (present perfect) makes sense since the effect is still continuing
as suggested by - have been .

Let me know if these helps!
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