since和for的用法：
since 用來說明動作起始時間，for用來說明動作延續(xù)時間長度;
eg：I have lived here for more than twenty years.
I have lived here since I was born.
for后面多接一段時間，而since后面則接一個時間點(diǎn)，若since后面也出現(xiàn)時間段，則在時間段后加ago;
eg： I have lived here for twenty years ago.
錯句：I have worked here since twenty years.
since句型：
It is +一段時間+ since從句，since從句要用一般過去時;
eg：It is two years since I became a postgraduate student.
相關(guān)推薦：2014年12月英語六級備考輔導(dǎo)
since 用來說明動作起始時間，for用來說明動作延續(xù)時間長度;
eg：I have lived here for more than twenty years.
I have lived here since I was born.
for后面多接一段時間，而since后面則接一個時間點(diǎn)，若since后面也出現(xiàn)時間段，則在時間段后加ago;
eg： I have lived here for twenty years ago.
錯句：I have worked here since twenty years.
since句型：
It is +一段時間+ since從句，since從句要用一般過去時;
eg：It is two years since I became a postgraduate student.
相關(guān)推薦：2014年12月英語六級備考輔導(dǎo)