两道语法

以下是引用qiuxiaofei在2003-11-6 19:50:00的发言：
(Just because King Alfred occupied and fortified London in 886 did not mean that he) also won the loyalty of its citizens:the invading Danes were well aware of this weakness and used it to their advantage in 893.
B.The fact that King Alfred had occupied and fortified London in 886 did not mean that he had
答案中只有B好些,但我不明白的是有时间状语"in+某某年"应该用一般过去时,难道也可以用过去完成时吗?

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在这里过去完成时是过去的过去，句中的意思也是表示过去的过去King Alfred occupied and fortified London 。有时候还是要看句意才能决定时态。公理也不是唯一的。


A little under a million years ago, the briny waters of the Baltic Sea began flooding into the cold North Atlantic:geologists are still debating (whether the flood was gradual or created a cataclysm).
C.about whether the flood was gradual or cataclysmic
D.whether the flood was gradual or cataclysmic
debate over/about是固定搭配,为什么C不对呢?


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debate 后面加从句的话不用over或者about