"Know this!"

[jemenake]

So, I do conversation over Skype with a Spanish teacher in Mexico, and I stumped him with this: I wanted to know what the imperative conjugations of "saber" were, and he said that he couldn't recall them. He said that they just don't use saber in that way in Spanish.

Now, I was able to, later, look up what imperativo saber is, but I still wonder, if you don't use saber in that way, how *do* you say something like:

"Know who the first president was for the exam"

Actually, I was talking to him about electric vehicles, and I was explaining "range anxiety" to him, and how EV drivers are admonished to "always know where a reachable charging station is".

How would you say something like that in Spanish? "Siempre esté seguro que sepa..." or something?

[AngelicaDeAlquezar]

Imperative form of "saber":
(tú) sabe
(vos) sabé
(usted) sepa
(vosotros) sabed
(ustedes) sepan

We do use the "saber" in imperative, but seldom.

Your example for "ustedes" (as we in Mexico would address a group):
- Sepan quién fue el primer presidente, para el examen.
In daily speech though, we would rather say "sépanse"; the "se" in this case only adds some sort of emphasis (maybe as if your teacher said "do know").
More colloquially though, we might say something like: "Hay que saber quién fue el primer presidente para el examen". "Hay que", an impersonal form to state what is needed, substitutes the imperative.

*edit* By the way, a Mexican teacher would most probably say "apréndanse quién fue el primer presidente para el examen".
This is closer to "know by heart", and also "se" adds an emphasis on the action.


Your second example can very well be expressed with the imperative of "saber": "Sabe (tú) siempre dónde puedes recargar la batería", but it might sound slightly artificial. You can use "está seguro [be sure] de saber siempre dónde..." or, way better, "asegúrate [make sure] de saber siempre dónde..."

[aleCcowaN]

No se olviden de aprender ...
No se olviden de estudiar ...
No vengan sin saberse bien ...
No vengan sin saber ...
Tengan (bien) claro ...
Es indispensable que sepan ...
Es fundamental que puedan contestar ...