Animating mc from left to right

Gd’day mates,

I have 4 mcs which are my buttons. eg. [1] , [2] , [3] and [4]
what i am trying to do here is to shift mc [1] and mc [2] to the left side and mc [3] mc [4] to the left side when click on mc [2].

how do i do that with just purely AS instead of motion tween?

Thanks.