Take another look at the sentence:

Vacuuming under the furniture, dusting the ceiling fans, and scrubbing the tile grout with a toothbrush, Jerry prepared the house for his ultra-picky mother-in-law.

When you list grammatical items, you must use parallel structure. Here, vacuuming, dusting, and scrubbing all begin participle phrases, so the list is parallel.

Go to the next sentence.

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