estaban trepando
-they/you were climbing
Imperfecto progresivo para el sujetoellos/ellas/ustedesdel verbotrepar.

trepar

Después de la primera noche... Y tuvimos un problema, porque los periodistas se estaban trepando y escalando la pared para entrar al cuarto de Paul.
After the first night, we had a problem, because the paparazzi were actually climbing up and scaling the wall to get to Paul's room.
Palabra del día
la cometa