什么现在完成时 现在完成时的结构 现在完成时要注意哪些
问题描述：
什么现在完成时 现在完成时的结构 现在完成时要注意哪些
答
现在完成时
指着眼于现在 强调过去的动作对现在造成影响
句型：This is the first/best/the only book that I have ever read.
It has been three years since I learnt English.
=it is three years since I leant English.
4过去完成时
是指过去的过去
Hardly /scarcely had I arrived at the station when the bus left.
No sooner had I arrived at the station than the bus left.
特例：hope,wish,expect,think,intend,mean,suppose用过去完成时表示"原本… had expected,had intended 表示本期盼,本打算
句型：No sooner than hardly/scarcely when
No sooner had he arrived at the station than the bus left