第1个回答 2009-06-02
i wouldn't have done it if i knew that.
第2个回答 2009-06-02
i should not have done it (if i know it earlier)
第3个回答 2009-06-05
Had I known this, I wouldn't have done it.
第4个回答 2009-06-02
I wouldn't do it if I knew.
第5个回答 2009-06-02
总结一下,
I wouldn't have done it if I knew earlier.