柠檬脾气个人GMAT语法笔记,综合Manhattan SC及 prep语法笔记
(5) 从未发生-过去式：（对过去的虚拟）
IF Past Perfect（过去完成时）, THEN Conditional Perfect（情态动词完成时）
IF Sophie HAD EATEN pizza yesterday, THEN she WOULD HAVE BECOME ill.
*.情态动词would/should永远不会出现在“if”从句中
4，5 主将从现
其他动词考点
一、助动词：be /do /have
1．若出现时态变化，则句子中助动词不能单独的使用
对I have never seen an aardvark, but my father has.
错I have never seen an aardvark, but last year my father did.
对I have never seen an aardvark, but last year my father saw one.此处就不能用has替代
2．助动词后省略的词一定要是原文之前出现过的 错Our cars were designed to inspire envy, and they are.
对Our cars were designed to inspire envy, and they do.
…are priced to sell and they do
前后时态，数量改变，都不能用省略
Note.省略而成的do, are, have都只能代表主动时态
二、情态动词 Can, could, may ,might, must, shall , should, will and would,
1.这些词在使用过程中不能相互替换。
有时候情态动词会与一些具有类似含义的动词发生重复，要避免。比如在有ensure等
强调必须、义务的句子，再用have to/must显得啰嗦。
2. Be to 在GMAT中永远是错误的，用will, 或者should 替代
