You'd better hurry.
句意：：你最好快一点.
句中'd better的是had better的省略形式.
'd 经常出现在口语中,一定要分清楚它代表哪个单词或短语.如：
You'd better say nothing of that.
句意：你最好对此事保持沉默.
句中的'd是 had的省略形式,had better do sth 意为：（建议）最好做某事
Yes,I 'd would like to come with you.
句意：是的,我愿意跟你一起去.
句中的'd是 would的省略形式,would like to do sth 意为：愿意做某事
One survey was done before they’d had finished building a new light rail system.
句意：在调查之前,他们已经完成了一个新的轻型城市轨道交通系统的建设,
句中的'd是 had的省略形式,had done sth 意为：(在过去某一时间前就已) 做完某事,即,这是过去完成时的结构.
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