CD wrote:
What about
X is better than Y vs.
X is better than Y is
OR,
He is smarter than she vs
He is smarter than she is
in general, the second 'is' is unnecessary, and should be omitted, UNLESS
1) it is
needed to resolve ambiguity, or
2) the two parts of the parallel construction are obnoxiously long, to the point where the parallel construction itself is difficult to follow without that extra little word.
neither 1) nor 2) is true in the cases above, so the first version of each is preferable.
comforting fact: the test will NOT require you to choose between two grammatically correct and sensible alternatives, unless one of the two is wordy to the point of ridiculousness.
so if you see two choices that differ ONLY in the presence/absence of a 'little word', it is very likely that the little word disposes of some sort of ambiguity. look hard.
if you have the o.g. verbal supplement, look at problem number 106, in which the correct answer really does differ from one of the alternatives by one little word (which eliminates the ambiguity present in the incorrect choice)
nb: don't post details of the o.g. problem here. thank you.