* if there is a subject-verb error, then either the subject or the verb will usually fall outside the underline. * in most parallelism errors, one of the two parallel constructions will be outside the underline. * in most pronoun errors, either the pronoun or its antecedent will be outside the underline. * in most two-part idioms (e.g. more ... than), one of the two parts will be outside the underline. --这功底和经验
perhaps i've misread this -- but, the beauty of language (and the reason why SC is hard for lots of people) is that there is definitely not "only one way for the sentence to properly read". almost any sentence can be written in a huge variety of ways, only one of which will actually be the correct answer. this observation accounts for (a) the fact that it's impossible to predict correct SC answers, as well as (b) the fact that it's actually possible for different writers to have different styles. (if it were true that sentences could only be written in one way, then different writing styles couldn't exist.)
in any given SC, four of the five choices will be wrong, but it's a huge mistake to think that there is One True Correct Way in which to write the sentence.