I’m not a teacher.
I know only following idioms with “tongue”:
hold (one's) tongue
- To be or keep silent.
lose (one's) tongue
- To lose the capacity to speak, as from shock.
on the tip of (one's) tongue
- On the verge of being recalled or expressed.
have (or speak with) a forked tongue
- To speak deceitfully; prevaricate or lie.
wooden tongue — see actinobacillosis
actinobacillosis: Definition from Answers.com
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