3、leave是瞬间动词，用于现在完成时时，不与for引起的表示一段时间的状语连用。
4、leave作“假期”解时是可数名词；作“准许，批准”或“辞别”解是不可数名词，其前不可加不定冠词a。
例句：
When I left they were all still hard at it.
我离开的时候他们都还在努力工作。
I have two leaves in three year.
三年内我有两次假期。
Why would he leave his car?
他为什么要丢弃他的车？
