Functional difference between a Dash (-) and comma (,)

[anshultomar]

Hi Ron,

In one of your SC session (Dec6,2012) you mentioned that dash (-) behaves differently from comma (,) in a way that Dash can set off entire sentence as "description", i.e as dash can connect two sentences whereas a comma can not (run on).

If I apply the same logic to the below question then I am left with option B and D but the explanation provided by Stacey in 10 July 14 session contradicts the above statement !!

Can I assume that even dash can not set off the entire sentence just like the comma?

[---]

Request you to please help.

[tim]

As per the forum rules, we need a verifiable source for the problem before we can deal with this question. If the question is not one of ours or one that is copyright-free, we will have to delete the question.

[anshultomar]

Hi Tim,

I am not sure about the source of the problem but I assumed it to be from GMAT Prep as this problem was discussed by Stacey in 10 July, 2014 SC session.

Regards,
AT

[tim]

If you have actually seen the problem on GMAT Prep, then post it in the appropriate forum. If you have no actual knowledge of the source of a problem, you are not allowed to post the question.

[RonPurewal]

in the problem you cited, the dashes are clearly used to set off an entire sentence. the interruption of the sentence is rhetorically effective because the "interrupting" part provides an explanation for one particular statement in the sentence.

of course this is a non-issue here, since none of that part is underlined.

[RonPurewal]

... and, since this is an OG problem, i'm deleting the problem (though preserving the discussion) and locking the thread. if you have pictorial evidence (= a screenshot) that the problem is actually in the free GMAT Prep software as well, feel free to post a new thread.