“flew” vs. “flue”

Reach for "flew" whenever you need the past tense of "fly"; reach for "flue" whenever the sentence is about a chimney, stove, or furnace's smoke duct.

The real distinction

This pair sounds identical but couldn't describe more different things — one is a verb form about past motion through the air, the other is a stationary noun naming a household or industrial duct — so the only realistic error is a spelling slip during fast writing, not a true mix-up in meaning. Since "flew" always appears as part of a verb phrase describing something that has already flown (a bird, a ball, an insult), while "flue" always appears as a noun that could take "the" or "a" in front of it (the flue, a clogged flue), checking which grammatical role the word is playing in the sentence settles the choice instantly. Chimney sweeps, HVAC technicians, and home inspectors use "flue" constantly and would immediately notice "flew" as an error in technical documentation, since the two words never do the same job in that specialized field's writing. Because "flue" is the less common of the two words in everyday writing, it's the one more likely to get autocorrected into "flew" by phones and word processors, so writers describing chimneys or furnaces should double check the word survived a spell-check pass intact. There's also a useful grammatical anchor: "flew" can never follow "the" or "a" the way an ordinary noun does — you'd never write "the flew" — while "flue" almost always does, appearing as "the flue," "a flue," or "this flue" in nearly every real sentence that uses it. Chimney terminology also distinguishes a flue from a full chimney: the flue is specifically the interior passage carrying smoke upward, while the chimney is the entire structure surrounding it, a distinction worth knowing for anyone writing home-repair or safety content where precision matters. Building codes in many regions specifically regulate flue diameter and material, so technical writing in that space treats the word with real precision rather than as a loose synonym for "chimney." By contrast, "flew" never carries any technical or regulatory weight at all — it's simply an ordinary irregular past tense, correct in any register from casual conversation to formal narrative prose, with no specialized field claiming it as their own the way heating and construction claim "flue."

Examples with “flew”

• The hawk flew low across the open field.
• Sparks flew as the blacksmith struck the anvil.
• She flew back home the moment she heard the news.
• The frisbee flew farther than anyone expected.
• Rumors flew around the office all afternoon.
• The plane flew through a brief patch of turbulence.
• Feathers flew as the pillow fight got out of hand.
• The javelin flew well past the previous record.

Examples with “flue”

• The old flue was clogged with decades of soot.
• A new liner was fitted inside the crumbling flue.
• Smoke curled up through the narrow brick flue.
• The technician inspected the flue before winter began.
• Cold drafts crept in through the unused flue.
• The stove's flue needed cleaning after the long season.
• Builders routed the flue up through the roofline.
• A cracked flue can let dangerous fumes back into the house.

Memory trick

"Flew" rhymes with "grew" and "blew," fellow irregular past-tense verbs describing something that already happened. "Flue" hides inside it the idea of "flow" — smoke flowing up and out through a chimney's hidden passage.