Usage and Grammar

Q. I’m troubled by this sentence: “She combed her hair, brushed her teeth, and was putting on her lipstick when the phone rang.” I think it should be reworded since the list does not have parallel construction. My friend disagrees. Is it correct as is, or is there a simple fix?

A. You are correct. In a series of verb phrases, any auxiliary verb must apply equally to all of the phrases. So that “was”—an auxiliary verb that helps to create the past-progressive tense—is a problem. You can fix it by adding a conjunction to break up the series: “She combed her hair and brushed her teeth and was putting on her lipstick when the phone rang.” CMOS 5.245 covers this issue (minus the lipstick). For more on progressive tenses, see 5.135.