SC: Brain logic behind the analysis

[westvanyo]

Good day MGMAT instructors and forum partners,

i have a question regarding the thinking process behind the analysis of SC questions. The question is the following:

When you read the SC sentence, you spot the errors right away when you are reading the sentence, or you have to wait to see the multiple choice answers to know what is wrong.

Thanks.

[StaceyKoprince]

It depends on the question. Sometimes, an error is irrefutable:
The cats is on the table. :)

Other times, you're really dealing with a preference, or a general rule that can have exceptions. Then, you think, "Hmm, I'm not sure... let me see what the other answers say."
Her letters to her sister, which were written last year, describe the preparations for her graduation party.

That one might look not-so-good at first, because most people would want the "which" modifier to be next to letters. This sentence structure, though, mimics the correct answer to a real GMAT question from the OG. When I first read it, I thought, Really? Let me go check...

But it turned out that that particularly setup was not an error - it appeared in the correct answer as well. Noun modifiers are supposed to be placed as close as possible to the noun they modify, which often means placing the modifier right next to the noun... but not always. :)