muck about
US /mʌk əˈbaʊt/
UK /mʌk əˈbaʊt/

1.
brincar, perder tempo
to spend time doing silly or unimportant things
:
•
Stop mucking about and get your work done.
Pare de brincar e faça seu trabalho.
•
The kids were mucking about in the garden.
As crianças estavam brincando no jardim.