- 理屈词穷 lǐqūcíqióng to not have a leg to stand onTo be unable to provide a convincing argument or to fall silent after being bested in a debate; literally, one's reasoning is flawed and words have run out.
- 词穷理尽 cíqiónglǐjìn at a loss for wordsUnable to find any more words or arguments to defend one's position; having exhausted both one's vocabulary and one's logic.
- 词穷理屈 cíqiónglǐqū to be at a loss for wordsTo find oneself with no more arguments because one's reasoning is weak or flawed; to be silenced by the lack of a convincing explanation.
- 词穷理绝 cíqiónglǐjué to be at a loss for wordsTo have nothing left to say and no logic left to argue; also written as [[词穷理尽|詞窮理盡|ci2 qiong2 li3 jin4]].
