MGMAT CAT

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MGMAT CAT

by sam117 » Tue Apr 24, 2012 11:06 am
Hi, I know this question has already been posted on this forum but my problem has not yet been addressed.


Geologists once thought that the molten rock known as lava was an underground remnant of Earth's earliest days, sporadically erupting through volcanoes, but they now know that it is continuously created by the heat of the radioactivity deep inside the planet.

A. was an underground remnant of Earth's earliest days, sporadically erupting
B.had been an underground remnant of Earth's earliest days and sporadically erupted
C.was an underground remnant of Earth's earliest days, which sporadically erupted
D.would be an underground remnant of Earth's earliest days that sporadically erupted
E.was an underground remnant of Earth's earliest days, having sporadically erupted

The OA is A. I do not understand why E is wrong, according to MGMAT: "In this choice, "having sporadically erupted" incorrectly places this modifier in the past tense, implying that lava no longer erupts through volcanoes." But isn't "having erupted" in the present perfect tense? and isn't this tense used for actions that started in the past but continue in the present? Please help. Thanks!

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by patanjali.purpose » Tue Apr 24, 2012 2:41 pm
sam117 wrote:The OA is A. I do not understand why E is wrong, according to MGMAT: "In this choice, "having sporadically erupted" incorrectly places this modifier in the past tense, implying that lava no longer erupts through volcanoes." But isn't "having erupted" in the present perfect tense? and isn't this tense used for actions that started in the past but continue in the present? Please help. Thanks!

Geologists once thought that the molten rock known as lava was an underground remnant of Earth's earliest days, sporadically erupting through volcanoes, but they now know that it is continuously created by the heat of the radioactivity deep inside the planet.

Lets ignore the 2nd clause after BUT and the introductory clause:

The molten rock known as lava was an underground remnant of Earth's earliest days, having sporadically erupted through volcanoes (this is our sentence)

Having tried before, Stephen knew the problems associated with rock-climbing. HAVING TRIED conveys PRIOR ACTION than the main action (meaning TRYING HAPPENED BEFORE KNOWING).

Similarly in the above sentence means ERUPTION HAPPENED BEFORE LAVA WAS REMNANTS. Is this the intended meaning? I am sure, you will say NO.

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by GmatKiss » Tue Apr 24, 2012 10:38 pm
IMO: A