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rat on

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Betray a comrade by giving information, as in He ratted on his best friend to the police. [Slang; early 1900s]

QUIZ
WILL YOU SAIL OR STUMBLE ON THESE GRAMMAR QUESTIONS?
Smoothly step over to these common grammar mistakes that trip many people up. Good luck!
Question 1 of 7
Fill in the blank: I can’t figure out _____ gave me this gift.
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.

How to use rat on in a sentence

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