oalimov wrote:
You should still use Present Perfect because the result of the earthquake is still present. So the answer should sound like this:
"Possibly, the earthquake have caused the building's collapse."
or
"The earthquake may have caused the building's collapse."
In my opinion "X may have caused" is more direct and concise than "possibly, X have caused".
Hi oalimov, don't forget the "may" in the first sentence. Your current sentence does not have subject/verb agreement.