Put two and two together/綜合而知

[movie]http://edu.sina.com.cn/en/2002-12-30/3_42-31-915-8267_20021230133157.rm[/movie]

定義：
　　make a correct conclusion on the basis of some facts
　　從一些基本事實中而得到正確的結論
　　
　　例句：
　　She told me she was getting married soon so when I saw her with that man, I put two and two together and figured out that he was her finance.
　　她告訴我說她要結婚了，所以當我看到他跟那個男人在一起時，我想他是她的未婚夫。