There are three main types of the conditional, with a number of variations within each type. In English, type 1 has a present simple in the “if” clause, and a future simple in the main clause. In Spanish, type 1 has an indicative present simple in the “si” clause and a future or present simple (indicative mood) in the main clause:
Si vienes pronto, iremos a la playa. If you come soon, we'll go to the beach.
Si llueve pronto, nos quedaremos aquí. If it rains, we will stay here.
The present simple in the main clause is common when the speaker has a high degree of certainty or when the main clause is a decision. Type 2 in English has a past simple in the “if” clause and a conditional tense in the main clause. In Spanish, type 2 has a subjunctive imperfecto in the “si” clause and a conditional tense in the main clause.
Si vinieras pronto, iríamos a la playa. If you came soon, we would go to the beach.
Type 3 in English has a past perfect in the “if” clause and a conditional perfect in the main clause. In Spanish, type 3 has a subjunctive pluscuamperfecto in the “si” clause and a conditional perfect in the main clause:
Si hubieras estudiado más, habrías aprobado. If you had studied harder, you would have
passed.
In addition to “si,” conditional sentences can be structured with “a no ser que” (unless),”a menos que,” “siempre que” (as long as), “con tal (de) que” (provided/providing that), “con la condición de que” (on condition that).
Te dejaré conducir, siempre que I will let you drive as long as you promise
prometas que vas a ser cuidadoso. that you are going to be careful.
Llegarás tarde, a no ser que te des prisa. You’ll be late, unless you hurry up.
The expression “in case,” as in “I’ll take an umbrella with me in case it rains, must be translated by “por si.”
Lo ordenaré todo por si viene mi madre. I’ll tidy everything up in case my mother
comes.
“In case of,” translates as “en caso de” in warnings:
En caso de incendio, romper el cristal. In case of fire, break the glass.
There are a number of variations that are very similar in both languages:
Si le odias, ¿Por qué fuiste con él? If you hate him, why did you go with him?
Si has terminado, puedes irte. If you have finished, you can go.
Si estás libre, podrías echarme una mano. If you are free, you could give me a hand.
“If ” and “I wish” translate as “ojala,” with a connotation of “hopefully,” This expression can be followed by a subjunctive present simple, a subjunctive imperfecto, and a subjunctive pluscuamperfecto:
Ojalá (ella) venga a tiempo If only (let’s hope) she comes in time.
Ojalá (él) nos ayude. If he will help us.
“Will” provokes a subjunctive present simple of the following verb, and “would” causes a subjunctive “imperfecto” to be used.
After “If,” when requesting something politely, “will” translates as the indicative present of “querer,” whereas “would” translates as the subjunctive imperfecto:
Si usted quiere esperar un momento. If you will wait a moment.
Si usted quisiera seguirme. If you would follow me.
