现在完成时 现在完成时: have/ has + 过去分词 1) 表示到现在为止已经完成或刚刚完 成的动作。 Now we have planted all the trees. He has just come back.2) 表示过去发生的动作, 但强调结果或对 现在的影响。 Have you had your supper? I have read the book twice already. 在以上两种用法中常跟already, notyet, never, just, before, ever, recently 等时间继续下去的状语。3) 表示过去已经开始, 持续到现在, 也 许还会继续下去的动作或状态，常与包 括现在在内的一段时间的状语连用。 He has studied English for 6 years. Mary has been busy since she came back from Hangzhou.过去分词的构成 1.直接加-ed。如：play-played 2.以字母e结尾的直接加d 。如：name- named 3.以辅音字母加y结尾的，变y为i
