Final answer:
An idiom is a phrase or expression that has a figurative meaning different from its literal meaning. The sentence that contains an idiom is: 'Brady will start singing at the drop of a hat.' In this sentence, the phrase 'at the drop of a hat' means that Brady is always ready and willing to start singing, without any hesitation or delay.
Step-by-step explanation:
An idiom is a phrase or expression that has a figurative meaning different from its literal meaning. The sentence that contains an idiom is: Brady will start singing at the drop of a hat. In this sentence, the phrase 'at the drop of a hat' means that Brady is always ready and willing to start singing, without any hesitation or delay.
Learn more about Idioms in English