Q: Sentence (1) Break down a proof.
Sentence (2) I broke my foot while playing hockey.. Word: break.
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A: different meanings

Q: Sentence (1) A working stiff.
Sentence (2) A lucky stiff.. Word: stiff.
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A: the same meaning

Q: Sentence (1) Estimates of the city's loss on that job ranged as high as a million dollars.
Sentence (2) I've got a job for you -- could you wash the dishes?. Word: job.
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A:
the same meaning