When does one use avec and when is it not necessary?

Question

In the sentence which I did not get correct it was shown as:On ne doit pas parler la buche pleine. My question is why is "with"/avec not used?

Accepted Answer

Hi Anne,
The expression is just -
ne pas parler la bouche pleine

Answer

I can't answer the "why" except for saying that's just the way it is in French. It used to be like this in English as well, and there are still some remnants of this even in today's English:

Hands up in the air, he was dancing like a madman. Of course, you could also say, "He was dancing like a madman with his hands up in the air", but even in English this doesn't flow as smoothly.