chenche8827 Wrote:Dear instructor
I have a second thought about c. when we add a comma before a connecting word such as "but",we should make sure that the sentence after "but"is a whole sentence;otherwise we should omit the comma. in this case,there is a comma before "but" so if we omit the same subject of the sentence,then we need eliminate the comma.Just like Ron's example:Sam washed his cloths and clean his room. here we can omit the same subject he or sam because there is no comma before and.However,In E,C this is not the case,we got a comma here.I am really confused,and I chose C just because of this reason.So please help me.
ya, this isn't *normally* the way such things are punctuated, but there are lots and lots and lots and lots of exceptions to punctuation rules.
fortunately, punctuation is NOT tested on the gmat.
basically, you should use punctuation as a guideline for understanding sentences, but you should NOT try to eliminate choices by using "punctuation errors". that is not something that is tested on this exam.
one less thing for you to worry about!