get on like a house on fire 很快就打得火热；一见如故；一拍即合；快速前进；进展顺利

【例句】
We got on like a house on fire. I wasn't sure my little brother and my boyfriend would like each other, but they actually get on like a house on fire.
我之前不确定我弟弟和我男朋友会不会合得来，但实际上他们一见如故，相处得很好。

I started on her some months ago, and she’s getting on like a house on fire, I shall win my bet.
我几个月前开始教她，她现在进步很快，我打的赌会赢的。