why dancing is used after to?
let's get down to dancing.
let's get down to work.
After to we need infinitive ,but dancing has ing

Vedi una traduzione

@samira_h

the infinitive works for desire. I want to work I want to dance.

however the concept 'let's get down to' a unique phrase. it's not a literal term. in that it is irregular it will behave irregularly.

let's get down to dancing really means.. let's stop what we are doing and get ready to begin what we came for.. to dance. we came for dancing. therefore let's get down to dancing.

we came for work. let's get down to working or let's get down to work.
or more likely: let's get down to working on this project.

cognitively as a native speaker I think of dancing as the action. dance is more of a command. work is an action and command. working is solely an action.

you could say let's get down to dance, but you would need to say it with great enthusiasm to make it sound natural.

whoo hoo let's get down to dance!!

even with enthusiasm it sounds like you are sitting on something high and you want to get down to dance.