OnlywhenIcheckedthepaperoncemore_________therewasamistake.A.IrealizedB

Only when I checked the paper once more _________ there was a mistake.A.I realizedB.did I realizeC.I had realizedD.had I realized

B解析试题分析：句意：只有我再次检查试卷时才意识到有一个错误出现了。这是倒装句，Only+状语从句放在句首时，主句用部分倒装。检查时发现的错误，检查和意识到几乎同时发生所以用过去式，故选B。考点：考查部分倒装的用法。点评：本题难度适中。本题对已学语法知识点的回顾，需要考生熟记倒装的各种情况。即学即练：Only then ________ the importance of English．A. I realized B. did I realize C. I had realized D. had I realized解析B：。在句首的only如果后面跟了副词、介词短语或从句等状语，则主句用倒装结构。如only后跟的是主语，就不用倒装结构了。

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