debes mantener

you must keep

→ deber
phrase Uncommon #10,990
you must keep Used to say that something should stay in a certain state or condition.
SP: Debes mantener la calma en una emergencia.
EN: You must keep calm in an emergency.

Siempre debes mantener el cuarto limpio.

You should always keep the room clean.

Debes mantener limpia tu pieza.

You must keep your room clean.

Debes mantener tus dientes limpios.

You must keep your teeth clean.

Debes mantener tu lealtad a la familia.

You must maintain your loyalty to the family.

Debes mantener tus zapatos limpios.

You must keep your shoes clean.

Aprende a reconocer cuándo te debes mantener callado y cuándo debes hablar.

Learn to recognize when you should remain silent and when you should speak.

Así que debes mantener la velocidad.

So you need to maintain your speed.

— El salario del miedo (1953)