Final answer:
To achieve parallel structure in the sentence, one should maintain a consistent pattern by using the same grammatical construction for each subject's preferences.
Step-by-step explanation:
The sentence can be rewritten to make its elements parallel by structuring them in a similarly consistent format for each subject and their respective preferences. Ideally, the sentence should maintain the same grammatical structure when listing different comedians or acting groups that each generation enjoys. An example of a rewritten sentence with parallel structure would be:
'My grandparents like the humor of Rich Little, Johnny Wayne and Frank Shuster; my parents enjoy the antics of Andrea Martin, Dan Aykroyd, and John Candy; but I prefer the comedy of Jim Carrey, Tom Green, and Brent Butt.'
This sentence maintains parallelism by using the same construction for each group's preferences, starting with the subject followed by an action verb ('like', 'enjoy', and 'prefer'), and then listing the entertainers. Additionally, it uses the proper names 'Johnny Wayne and Frank Shuster' instead of 'Wayne and Shuster' to match the pattern of listing full names as in 'Andrea Martin, Dan Aykroyd, and John Candy.' By doing so, it improves the sentence's clarity and consistency.