One of the telltale signs: inconsistencies, such as when someone is telling you no and shaking his head yes, or saying he regrets something while using an unremorseful tone.

其中揭秘的迹象有：矛盾不一，比如一个人告诉你说不是却又点头，或者说他后悔某事却是用一种并非懊悔的口吻。

youdao

“Yes. No. It depends what you mean, ” he said.

他回答说：“可以说幸福，也可以说不幸福，这要看你指哪方面了。”

youdao

"If somebody tells you you have no pants, just say you forgot, and yes it's cold, yes it's unfortunate," he said.

如果有人告诉你你没穿裤子，就说你忘了，的确很冷，忘记穿裤子真的很倒霉。

youdao

"It looks very good that we come together (do a deal), it just takes a little bit of time because it's a situation where you cannot say yes or no immediately, " he said.

BBC: Ralf 'keen to stay put'