Q: Sentence (1) Reduce a problem to a single question.
Sentence (2) The cells reduce.. Word: reduce.
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A: different meanings

Q: Sentence (1) Don't underestimate the danger of such a raft trip on this river.
Sentence (2) He underestimated the work that went into the renovation.. Word: underestimate.
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A: the same meaning

Q: Sentence (1) Extend my greetings.
Sentence (2) Extend the loan.. Word: extend.
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A:
different meanings