Some conjunctions bring the subjunctive with them:

• para que — so that — always takes the subjunctive: Voy a hablar despacio para que todos me entiendan. — I'm going to speak slowly so that everyone understands me.
• With no new subject, use para + infinitive: Estudio para aprobar el examen. — I'm studying to pass the exam.

Aunque (although, even if) can go either way, and the mood changes the meaning:

• with the indicative, it states a fact: Aunque es caro, lo voy a comprar. — Although it's expensive (and it is), I'm going to buy it.
• with the subjunctive, it means even if — it isn't known yet, or it doesn't matter: Aunque llueva, vamos a ir a la playa. — Even if it rains, we're going to the beach.

Three more that always take the subjunctive: antes de que (before), sin que (without) and a no ser que (unless).