Q: Sentence (1) Bad luck caused his downfall.
Sentence (2) Gilbert had some bad luck yesterday -- he got pick-pocketed and lost fifty dollars.. Word: luck.
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A: the same meaning

Q: Sentence (1) He suffered from fatigue and emotional tension.
Sentence (2) Tension holds the belt in the pulleys.. Word: tension.
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A: different meanings

Q: Sentence (1) He rode into the mouth of the canyon.
Sentence (2) She wiped lipstick from her mouth.. Word: mouth.
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A:
different meanings