影视英语口语:忘记要说啥

“忘记要说啥”在英语口语里能怎么说？

普通口语：forget what to say
地道口语：lose the train of thought

素材来源：另类童话色彩《灵指神探》
剧情简介：
Ned把Chuck带回了他的店子里，跟她约法三章说两个人绝对不能有肢体上的接触，不然她会丧命。Chuck小郁闷，说我想拥抱你都不行的么？......

Chuck: I can't even hug you? What if you need a hug? A hug can turn your day around.
Ned: I'm not a fan of the hug.
Chuck: Then you haven't been hugged properly. A hug is like an emotional Heimlich: they put their arms around you and give you a squeeze and all your fear and anxiety goes shooting out of your mouth like a big, wet wad and you can breathe again.
Ned: That's fine for someone else to do if I'm choking on something other than emotion, but you can't touch me.
Chuck: So a kiss is out of the question?
Ned: I lost my train of thought.