We offered three possible reasons why they were opposed, and allowed respondents to choose as many as applied.

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Forest conservationists, schooled in failure, rattle off a list of possible reasons why.

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There are at least two possible reasons why this might be so.

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There are many possible reasons why the envelope-pushing jet has experienced problems.

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There are several possible reasons why, he explained.

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Broadly, these categories covered how widespread a particular behaviour pattern was if it was present at a site, and possible reasons for why it was not there if it was absent.

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There are only two possible reasons for why a gadget freak like you would want a cheap phone: you're either a very sensible person (who probably got mugged once), or you're saving up for the phone of your life.

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