run wild
US /rʌn waɪld/
UK /rʌn waɪld/

1.
crecer sin control, desbocarse, desatarse
to grow or develop without control or limits
:
•
The children were allowed to run wild in the park.
Se permitió a los niños correr libremente por el parque.
•
His imagination often runs wild when he's writing stories.
Su imaginación a menudo se desboca cuando escribe historias.