cardboard

US /ˈkɑːrd.bɔːrd/
UK /ˈkɑːrd.bɔːrd/
"cardboard" picture
1.

cartón

a stiff material made from paper pulp, typically used for making boxes and other containers

:
The moving boxes were made of thick cardboard.
Las cajas de mudanza estaban hechas de cartón grueso.
She cut a piece of cardboard to use as a base for her model.
Cortó un trozo de cartón para usarlo como base para su modelo.
1.

plano, endeble

lacking depth or substance; flimsy or unconvincing

:
The characters in the movie were so cardboard, I couldn't connect with them.
Los personajes de la película eran tan planos que no pude conectar con ellos.
His excuse for being late was rather cardboard.
Su excusa para llegar tarde fue bastante endeble.