Expressing condition and purpose with the subjunctive

Some key phrases or key words denote purpose and condition or contingency, much like pending action clauses. These phrases will always require the use of the subjunctive because they express pending activity or some sort of desired end result.

Ex: I study hard so that I get good grades.

My purpose for studying is indicated: I want to get good grades. They are my desired end result / my reason for doing what I do.

Some key phrases which indicate condition, purpose, or a desired end result are:

Para que – so that, in order that

A menos que – unless

En caso de que – in case

Con tal de que – provided that

Again, these key phrases will need to be paired with the subjunctive.

Siempre escribo muchos apuntes en los Post-Its en caso de que yo no recuerde algo.

I always write lots of notes on Post-Its in case I don’t remember

something.

La profesora habla claramente para que sus estudientes comprendan lo que dice ella.

The professor speaks clearly so that her students understand what she says.

Ellos no van a hacer nada a menos que el jefe les diga que sí.

They’re not going to do anything unless the boss tells them to/ tells them so.

Yo traeré música a la clase con tal de que los estudiantes quieran escucharla.

I’ll bring music to class provided that the students want to listen to it.