Breakdown of Læg mobilen væk, mens vi spiser aftensmad.
Questions & Answers about Læg mobilen væk, mens vi spiser aftensmad.
Læg is the imperative form of lægge, so it is used for a command: Put ... away.
Just like in English, the subject is usually omitted in commands. So the full idea is really something like (You) put the phone away.
In Danish, the same imperative form can be used whether you are speaking to one person or more than one person.
This is a very common Danish distinction.
Lægge means to lay / to put something down. It usually takes an object: Jeg lægger mobilen på bordet = I put the phone on the table.
Ligge means to lie / to be lying. It does not mean actively placing something: Mobilen ligger på bordet = The phone is lying on the table.
So in this sentence, læg is correct because someone is being told to actively put the phone away.