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growing0424

Cynth1aC 发表于 2016-10-3 01:27
总结给一些和我一样，在A与B之间纠结的孩纸，希望能有所帮助
（一）grains of sand or of pebbles  vs.  gr ...

辛苦了！解释的很清楚！谢谢！

LingNie1988

"flecks of ... detritus" is plural, so the COMPARISON, in order to be properly parallel, should involve another plural noun. (this should be especially clear here, since there's a singular/plural split in the other half of the comparison.)

you should compare "flecks of ... detritus" with the plural "grains of...", not with the singular "a grain of..."

this eliminates (d) and (e).

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the part following "are generated WHEN" should be a CLAUSE, with a principal subject and verb.

in (c) and (d), there is no such verb. (the intended verb is swallowed up within a "which" modifier, leaving no main verb for the clause.)

so (c) is gone.

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in (a), "of pebbles" doesn't make sense (by parallelism, this would imply "grains of pebbles", which is nonsensical).
also, "burn up speeding" is unclear and awkward.

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last man standing is (b)