句子结构复杂

句子可能由多个部分组成，包含多个从句，如定语从句、状语从句、名词性从句等。例如：“The problem is that as technological progress becomes more incremental, diffusion also slows, since companies have less incentive and face less competitive pressure to upgrade.”

标点符号

标点符号如逗号、破折号、分号等的使用可能会改变句子的意思，需要仔细分析。例如，两个逗号形成的插入语可能会改变句子的主要结构。

连词

并列连词如and、or、but、yet、for等，以及从属连词如which、that、when、how、if等的使用，可能会使句子结构更加复杂。例如：“After six months of arguing and final 16 hours of hot parliamentary debates, Australia's Northern Territory became the first legal authority in the world to allow doctors to take the lives of incurably ill patients who wish to die.”

介词

介词引导的介词短语在句子中可充当定语、状语等修饰成分，需要准确理解介词短语的含义。例如：“The full import may take a while to sink in...”

长距离依赖

句子中可能包含长距离依赖关系，需要理解句子各部分之间的逻辑关系。例如：“The Greeks assumed that the structure of language had some connection with the process of thought, which took root in Europe long before people realized how diverse languages could be.”

修饰成分

句子中可能有多个修饰成分，如定语、状语等，需要仔细分析这些成分的作用和位置。例如：“We are thus led to distinguish, within the broad educational process which we have been so far considering, a more formal kind of education—that of direct tuition or schooling.”

建议：

在复习过程中，多读一些考研英语的长难句，注意分析句子的结构、标点符号、连词和介词的使用。

通过做练习题和模拟考试，提高自己应对长难句的能力。

如果遇到不理解的句子，可以查阅相关资料或请教老师，确保自己真正理解句子的含义。