It's a long time since they left.

　　他們已經(jīng)離開(kāi)很久了。

　　It's been two weeks now since she called.

　　她到現(xiàn)在已經(jīng)有兩個(gè)星期沒(méi)來(lái)電話了。

　　I had been out since I was 17.

　　我從17歲起就公開(kāi)我是同性戀。

　　The children are completely out of control since their father left.

　　這些孩子自他們的父親離開(kāi)后就無(wú)法無(wú)天了。

　　It's been an age since we've seen them.

　　我們有很長(zhǎng)一段時(shí)間沒(méi)有見(jiàn)到他們了。