It was when searching for the lost book whose cover was missing a secret letter
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It was when searching for the lost bookwhose cover was missing ______ a secret letter addressed to his mother.
| A．what he found | B．until he found |
| C．that he found | D．he had found |
试题答案
【答案】
C
【解析】考察强调句型。本题是一个强调句型，强调的是时间状语when searching for the lost book whose cover was missing，强调句型的后半句使用陈述语序。故C正确。