Hi
You must have seen people who sort of shake their one leg when they sit on a chair or in a sofa–the leg moves up and down. My class students do it a lot. So, could you please tell me if the following sounds OK and natural to you?
Tom
Hi Tom,
I’m not aware of this happening, to be honest. But if people do it and you don’t want them to do it, by all means say: Don’t shake your leg.
Alan
Your sentence sounds perfectly natural to me, Tom. Personally, I’d never dream of saying that to anyone, though. In fact, I make this kind of unconscious movement myself often enough. Of course, if I’m sharing a bench, for example, I try not to, but then in those cases I’m particularly self-conscious and find it easier to control my movements.
Hi,
Just another point related to the leg movement - there is an expression: Shake a leg! This means: Get a move on/Hurry up/Get started.
Alan
One more synonym for the expression-step on it! :lol:
P.S. Welcome back, Conchita. It’s nice to see much of you again!
Hi Tom
In my opinion, it would be more typical to describe this particular unconscious habit with the verb ‘bounce’ rather than ‘shake’.
Rather than using a direct command/request, you might also mention the disturbance more humorously. Can you think of a way to do that? A way which would be suitable for your group, Tom?
If you are teaching an English class, you might consider making use of the person who is bouncing/shaking their leg in order to teach the whole class what the words “shake a leg” mean – both literally and idiomatically. :lol:
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I’m happy to see you back too, Conchita! 
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