例58　The notion is that people have failed to detect the massive changes which have happened in the ocean because they have been looking back only a relatively short time into the past.

【结构分析】这句话是个典型的表语从句，句子的主干是The notion is that...，后面表语从句，表语从句的主语是people，动词是have failed to detect，宾语是the massive changes，后面是定语从句which have happened in the ocean，后面是状语从句because they have been looking back only a relatively short time into the past。

【亮点回放】此句话的亮点在于各种从句的连环相套，表语从句套定语从句，定语从句后面又套上状语从句。

【核心词汇】

the notion　意思就是说

massive changes　巨大变化

looking back　往回看

only a relatively short time　过去一小段时间

【参考译文】意思就是说人们没有发现海里发生的巨大变化，因为他们相对来说只看了过去一小段时间。