初中·課本中不會教你的 543　It's/has been+一段時間+since從句

543　It's/has been+一段時間+since從句

　這種句型意為“自從……起做某事已經(jīng)一段時間了”。該句型中的since 從句通常用一般過去時。要注意的是，如果since 從句中的謂語動詞是come, stop, leave, arrive等非延續(xù)性動詞，句意為肯定，順著翻譯即可；如果是be, stay, meet, smoke, live等延續(xù)性動詞，則要翻譯成否定意思。

It is just a week since I arrived here. 我到這里才一個星期。

It is nearly twenty years since I lived in Yangzhou. 我離開揚州已經(jīng)近20年了。（不在揚州 ）

It's been years since I enjoyed myself so much. 我已經(jīng)有很多年沒有那樣痛快過了。

It is five months since I didn't smoke. 我戒煙已經(jīng)5個月了。（不吸煙 ）

It is six years since he joined the army. 他參軍已經(jīng)6年了。

It has been ten months since she left home. 她離開家已經(jīng)10個月了。