Doubts are best clarified in class

Preparing for GMAT is no child's play. And definitely not the verbal section of the GMAT. Iam sure many of you there agree with me.

The intricacies of sentence corrections are better understood when you are made to think with the sentence( for godsake its not just math that involves thinking)

Your problems with sentence correction will be over the day you start thinking with grammar. Cos there is no grammar separate form meaning and no meaning separate from accepted knowledge- philosophical or scientific.
When you with a verbal expert, you are made to think with the sentence.

Here's an example

The set of propositions which was discussed by the panel have been published in the society journal.

A. which was discussed by the panel have been
B. which were discussed by the panel have
C. that was discussed by the panel was
D. which were discussed by the panel has
E. discussed by the panel has been

The set ( of propositions that were/are discussed by the panel) was/ has been published in the society.
Bracket out all word groups- the prepositional phrase- has been bracketed out. The set was/has been-both are right, since no specific time referenece.

The point here is that relative pronoun which/that refers to propositions and not 'the set'. Hence are/were/ have been must refer to propositions and not 'the set'

Hence we narrow down to E. drop the ' which are'/ that are...wordiness.

The sentence correction tip you gave me is good.
No need, the sentence correction tip that you gave me is good.

More thoughts
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