There are several ways in which the conditional is used in Spanish.  The connection among the conditional uses of verbs is that they don’t refer to events that definitely or necessarily have happened or are happening. In other words, the conditional tense refers to acts that can be seen as hypothetical, as we will see. For those wo speak english, it will be easy to apply it, because in most cases we can translate it as “would  verb form”. Let´s see some examples to clarify each use:

1- Describing an act that depends on a condition:

Si tuviese dinero, me iría de compras. (If I had money, I would go shopping.)  The condition to fulfill the action is having money.

2- In a dependent clause following a main clause in the past tense:

Dijo que nos sentiríamos mal tras tomar la medicina. (He said we would feel sick after taking our medicine).

3 – To indicate future time within the past:

Dijiste el año pasado que iríamos de vacaciones este verano. ( You told us last year that we were going on holiday next summer.)

4 –  To indicate probability, speculation or conecture in past time, or a concrete situation:

¿Donde estaría mi hermana ayer? Estaría en casa. (Where do yoy think my sister was last night? She was probably at home.)

¿Hablarías español en Irlanda? No, hablaría inglés. (Would you speak spanish in Ireland? No, I would speak English.

5- To politely make requests, state desires or ask for advice:

Desearía un vaso de agua. (I would like a glass of water.)

¿Usted cual elegiría en mi lugar? (Which one would you choose being me?)

We need to pay special attention to the Real vs. Unreal conditions.

A real condition is one which may actually come about or at least there is a possibility; in Spanish, the indicative is normally used both in the “if”clause and in the main part of the sentence:

Si nieva mucho, no iré a trabajar. (If it snows a lot, I won´t go to work.)

Si llegas tarde, te quedarás sin cenar. (If you come home late, you´ll have no dinner.)

In contrast, an unreal or contrary-to-fact condition is one which will not come about or is viewed as being completely hypothetical. In this case, the “if” clause in normally in a past subjunctive tense, and the main verb is in a conditional tense.

Finally, let me show you one of the best examples I know about unreal conditions. This is a poem by Angel Gonzalez, a great example of what we have been talking today. Hope you enjoy it!