如何用英语表达我明白了

1、I see 英 [a? si:] 美 [a? si]我明白了。

例句：Oh! I see.; Oh! Now I understand. 哦，我懂了。

2、I know。

例句： By the end of that first year, I knew how totally unsuited we were to each other.到了第一年年底，我明白了我们俩根本不般配。