影视英语口语:当我不知道啊

“当我不知道啊”在英语口语里能怎么说？

初级口语：I already know.
地道口语：Tell me about it.

素材来源：《身为人母》
剧情简介：Sarah是个居家作家，但主要的工作则是带女儿。在社区的游乐场，她同别的主妇表面上合得来其实格格不入。接着，她认识了被其他妈妈们称为白马王子的年轻爸爸……

【台词片段】
Brad: You guys come here a lot?
Sarah: No, just the last few weeks. I usually go to the one over on Harris, with the big wood things, you know, and the slide across.
Brad: Yeah, we actually rent a house right around the corner from there on Ashforth. That ice cream truck never leaves. Such a nightmare.
Sarah: Yeah, Tell me about it.