题目
Scientists think that the continents ________ always where they ________ today.A. aren't; areB. aren't; wereC. weren't; areD. weren't; were
Scientists think that the continents ________ always where they ________ today.
A. aren't; are
B. aren't; were
C. weren't; are
D. weren't; were
题目解答
答案
C. weren't; are
解析
本题考查动词时态和主谓一致的正确使用。解题关键在于：
- 判断主句和从句的时态关系：主句中的
think为现在时，但宾语从句描述的是过去发生的事实，需用过去时。 - 区分时间概念：第一空描述“过去的情况”，第二空对应“现在的位置”，需结合时间状语
today选择正确时态。
第一空分析
- 主语为复数
continents，动词需用复数形式。 - 句意强调“过去并非总在固定位置”，应使用过去时
weren't。
第二空分析
where they ________ today中today表明是现在时间，需用现在时are。