Learn Spanish (Spain): Para esta misión confidencial, deberías ser muy discreto. - For this confidential mission, you should be very discreet.

In Spanish, using the conditional tense of deber (like deberías) is the standard way to give advice, translating directly to "you should". If we used the present tense debes ("you must"), it would sound like a strict obligation or command rather than a helpful recommendation.

Does deberías always need to be followed by an infinitive verb like ser?

Yes! When using modal verbs like deber (should/must) or poder (could/can) to give advice, they are always followed directly by an infinitive (the unconjugated form of the verb). Here, deberías ser simply means "you should be".

Why does this sentence use para instead of por?

We use para here because it expresses purpose or intended use. It sets up the specific goal or context ("For this confidential mission...") that requires the person to be discreet. If you used por, it would incorrectly mean "Because of this confidential mission".

Would the word discreto change if I were speaking to a woman?

Exactly. Discreto is an adjective describing the person you are talking to. If you are addressing a woman, you must change it to discreta. If you were talking to a group of friends (using the plural vosotros), it would be discretos and the verb would change to deberíais.