The Verbivore

Did you know James Madison was the smallest President, at 5"4' and 100 lbs?

Richard Lederer spoke this afternoon at Mira Costa College. He's a linguist with San Diego ties, and previously hosted A Way with Words. He talked mainly about US Presidential trivia, in promotion of his newest book. But he also made sure to include some grammatical jokes, like: What's the difference between a cat and a comma? A cat has claws at the end of its paws, and a comma has a pause at the end of its clause.

I had to leave after the talk's first half--writing called--and didn't get to ask my question. Which is: "What part of speech is 'to smoke' in the sentence 'I stopped to smoke.'?"

It came up in my TESOL Grammar class. My professor solicited opinions from other Linguistic experts. The most likely explanation was that "to smoke" is an adverbial phrase, with the sentence having deleted an assumed phrase, with "I stopped (in order) to smoke." But the responses my professor received were so varied that I would have been interested to hear Dr. Lederer's response.