One expression in Urdu (Saanp soong jana)

Hi

I would like to discuss with you an expression from my language, Urdu.

Saanp soong jana

saanp–snake
soong–smell
jana–to do

The literal meaning of the expression is to smell a snake, which is completely different from to smell a rat.

When some emotional and loud person either stands corrected in front of many or gets confused terribly or becomes frightened and as a result [color=red]suddenly becomes quiet, we use this expression–sometimes ironically and sometimes otherwise. For example, yesterday one of our colleagues laid odds that the word grammar is spelled as "grammer–and when a dictionary was opened he "smelt a snake’–I mean, his emotions suddenly petered out and he became quiet–a perfect situation to use our expression.

So, do you think you could tell me an expression or so which could be the substitute of the said one??

I hope I have not given you many qualifications?

Tom

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He fell silent.
.

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I don’t know if this carries exactly the same sense, but you could also say “He clammed up.”
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