speechless
US /ˈspiːtʃ.ləs/
UK /ˈspiːtʃ.ləs/

1.
sin palabras, mudo
unable to speak, especially as a result of shock or strong emotion
:
•
She was left completely speechless by the unexpected proposal.
Se quedó completamente sin palabras por la propuesta inesperada.
•
He was speechless with rage.
Estaba sin palabras de rabia.