I believe you are mentioning MGMAT SC
in the context of maintaining Parallelism for Linking Verbs. ( Verbs that express the condition of the subject rather than focussing on the action eg.smell, taste, resemble etc ).
Both Sides of the Linking verbs should be parallel as in the above example.
Other examples could be:
Correct: A good deed reflects good character
Incorrect: A good deed reflects having good character.
In the incorrect version the two sides of 'reflect' are not parallel, hence incorrect.
Hope this helps.
Please give me kudos, if you like the above post.