完成时since和for的用法,要求简洁易懂.不要发一大堆例:These foreign students have lived in China for two years.These foreign students have lived in China since two years ago.

完成时since和for的用法,要求简洁易懂.不要发一大堆例:These foreign students have lived in China for two years.These foreign students have lived in China since two years ago. since 和 for 在完成时中用法的区别 for和since的用法 since和for用法 since和for的区别用法 since for的具体用法 since与for的用法 for和since的用法since时间后要加ago吗?还是for后加ago? 现在完成时since和for的用法,要具体的讲解 Because , Since , . As , For 的意思和用法 Because ,Since ,.As ,For 的意思和用法 during over since for的用法和时态 像as,since,for,等等介词的意思,和用法, since、for和from的区别区别加用法 现在完成进行时中since和for的区别,什么时候用since 什么时候用for since和for后面分别跟什么?在完成进行时中since和for的区别，什么时候用since 什么时候用for .since和for后面分别跟什么？ 用since 和 for完成句子 since的意义和用法 when和since的用法