Learn Spanish (Latin America): Si el teclado falla, hay que apagar el sistema. - If the keyboard fails, you have to turn off the system.

In Spanish, when you talk about a real or very possible condition using si (if), you use the present tense for the 'if' part of the sentence. Even though the keyboard failing might happen in the future, we still say Si el teclado falla (If the keyboard fails) in the present tense, just like we do in English!

Why do we use hay que instead of tienes que to say 'you have to'?

Hay que is used to express a general rule or something that must be done, without pointing at a specific person. It translates closely to 'one must' or a general 'you have to.' If you wanted to tell a specific person that they personally need to turn the system off, you would use tienes que apagar instead.

Why is it el sistema and not la sistema, since it ends in an 'a'?

Words that end in -ma are often exceptions to the rule that words ending in 'a' are feminine. Many of these words come from Greek and are actually masculine, which is why we use el. Other common examples are el problema, el tema, and el idioma.

Can apagar be used for turning off other things besides a system?