for和since的区别

单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,*,*,for,和,since,的区别,Since,用来说明动作起始时间，,for,用来说明动作延续时间长度。,I have lived here,for,more than twenty years.,I have lived here,since,I was born.,My aunt has worked in a clinic,since,1949.,Some new oilfields have been opened up,since,1976.,I have known Xiao Li,since,she was a little girl.,My brother has been in the Youth League,for,two years.,I have not heard from my uncle,for,a long time.,John has been here in China,since,two weeks ago.,Communications across the Atlantic have developed steadily,for,one hundred years.,He has been talking about the accident,since,it happened two hours ago.,I have worked hard with my English,for,all the three senior high years.,English grammar has not changed much,since,the time of Shakespeare.,CNN has been on the air,for,more than fifteen years.,注意：并非有for 作为时间状语的句子都用现在完成时。,I worked here,for,more than twenty years.,(我现在已不在这里工作。),I have worked here,for,many years.,(现在我仍在这里工作。),小窍门：当现在完成时+一段时间，这一结构中，我们用下面的公式转化，很容易就能排除非延续动词在完成时中的误使。,1)(对)Tom has studied Russian,for,three years.,=Tom began to study Russian three years ago,and is still studying it now.,2)(错)Harry has got married,for,six years.,=Harry began to get married six years ago,and is still getting married now.,显然，第二句不对，它应改为 Harry got married six years ago.或 Harry has been married for six years.,