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Use "lightspeed" in a sentence
"Armstrong's TTX displays a 'lightspeed' look by Kenny Scharf."
"I even managed to find the willpower to submit a short story to Lightspeed Magazine (which was rejected about an hour ago; talk about lightspeed)."
"Today, it pitched a fit at me and drew a line in the sand structurally, telling me (in essence) that I can't make it skip ahead in the narrative to kill some time for sub-lightspeed-travel, thank you very much, and I can just suck it up and write that part of the book."