You must be back by 10 o'clock. - Debes volver antes de las diez.
You must be back by 10 o'clock.
Debes volver antes de las diez.
Seeing that you're not surprised, I think you must have known. - Viendo que no estás sorprendido, creo que debes estar al corriente.
Seeing that you're not surprised, I think you must have known.
Viendo que no estás sorprendido, creo que debes estar al corriente.