1. My brain doesn't work. 我搞不清楚.
如果讲话讲到一半舌头打结, 或是讲到不知所云, 就可以说 My brain doesn't work. 或是有时候你在跟人家讨论一个问题, 这个答案你也许知道, 但偏偏就是想不起来, 这时你可以说 I don't recall (我想不起来) 或是讲这一句: My brain doesn't work. 通常我偏爱后者, 因为我觉得它形容的很传神. 当然你也可以用现在进行式, My brain is not working.
记得有一次老美问我 How are you doing? 结果我一边想 I am good, 一边想 not much, 结果说成了not good, 老美都快笑死了, 结果我就只好很尴尬地说了一声. My brain doesn't work, 所以这句话的用法还真不少吧!