考研同义词改写如下：

important ：crucial, significant, vital, essential, critical, fatal, concerned, necessary

common ：universal, ubiquitous, general

abundant ：ample, enough, usually, frequently

surprise ：startle, astound, astonish

enthusiasm ：zeal, fervency

quiet ：tranquil, serene, silent, calm

expensive ：high price, unaffordable, exorbitant

resolve ：handle, tackle, deal with, cope with, dispose, address

prosperous ：flourish

idle ：lazy

if ：whether, in case, provided, providing

这些同义词替换可以帮助你在考研写作和阅读中更丰富地表达思想，避免重复使用同一个词汇，使文章更加生动和有趣。建议你在准备考研时，多积累这些同义词，并在实际应用中灵活运用。