全国大众英语测验语法——比较since和for
Since用来申明举措肇始时候，for用来申明举措一连时候长度。
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.
留意：并非有for作为时候状语的句子都用现在完成时。
I worked here for more than twenty years.
(我现在已不在这里义务。)
I have worked here for many years.
(现在我仍在这里义务。)
小诀窍：当现在完成时+一段时候，这一构造中，我们用下面的公式转化，很随便就能拂拭非一连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.

关键字：英语四级测验语法 英语三级测验语法 大众英语测验 大众英语品级测验 大众英语测验时候