[译] 他在二十天内写完了一本小说，真令人吃惊。
[误] It was surprised that he finished writing a novel in only twenty days.

[正] It was surprising that he finished writing a novel in only twenty days.
[注] surprised 表示"感到吃惊的"，其主语应该是人，而 surprising 表示"令人吃惊的"，其主语应该是物或某件事情。所以误句中的 surprised 应改成 surprising。