考研中常用的替换词可以分为几大类，包括：
基本词汇的替换
good -> positive, favorable, rosy, promising, perfect, pleasurable, excellent, outstanding, superior
bad -> dreadful, unfavorable, poor, adverse, ill
many -> numerous, a host of, a multitude of
高级词汇的替换
important -> crucial, significant, vital, essential, critical, fatal, concerned, necessary
common -> universal, ubiquitous
numerous -> innumerable, countless
tremendous -> enormous
outdated -> obsolete, anachronistic
ephemeral -> transitory
特定场景下的替换
（an army of, an ocean of, a sea of, a multitude of, a host of, many, if not most） -> numerous, a host of, a multitude of
这些替换词可以帮助你在考研英语写作和阅读中更加精准和生动地表达思想，避免重复使用同一个词汇，使文章更加丰富和有趣。建议你在准备考研时，多积累这些替换词，并在实际写作和阅读中多加练习。