Open your mouth ... What idioms are there?

be agape and tongue-tied

Pronunciation zhāng küu Jie shé

Interpretation of the tongue: the tongue cannot rotate. I can't speak with my mouth open. Describe a clumsy argument, or become speechless because of nervousness and fear.

The killer thought it sounded like an iron bar hitting him on the head. He turned to look, panicked and tongue-tied. (Qu Bo's "Lin Yuan" Volume 28)

Synonyms are speechless and gaping.

Antonyms are eloquent and endless.

give a lecture

Pronunciation zhāng küu diào shé

Interpretation refers to making a speech.

Source yin's "Jing Shu Xu Kuang Sheng": "If you open your mouth and spit out your tongue, it is called slander; It is difficult to bow your head and avoid things. "