CONDITIONAL

Conditional
The conditional is formed using the modal"would" in front of an infinitive (dropping the word "to"). The conditional is used especially in three contexts:
1) Politeness

• I would like the menu, please.
• Would you have a couple of minutes for me?

2) To indicate the "future within the past":

• She said she would come to the party.
• I thought he would arrive before me.

3) In hypothetical constructions with "if." When "if" is followed by the preterit or the subjunctive, the conditional is expected in the second clause:

• If I had the time, I would do my homework.
• If you told me the truth, I would believe you. The "if" of hypothetical expressions can be implicit:
• In your position (= if I were you), I wouldn't have stayed.

CONDITIONAL SENTENCES Cuando deseas hablar acerca de una "posible" situación y sus resultados, debes utilizar una oración condicional. Observa estos ejemplos: If people invite you to a party, they expect you to come properly dressed.(Si te invitan a una fiesta, se espera que vayas correctamente vestido/a) If I wear the green jacket, it'll go with my new shoes.(Si uso la chaqueta verde, ésta hará juego con mis zapatos nuevos) En este tipo de oraciones condicionales existe una posibilidad real de que suceda lo que en ellas se expresa. Básicamente, existen DOS tipos de estructuras:

CLAUSULA CONDICIONAL IF + present simple CLAUSULA PRINCIPAL present simple

Se usa este tipo de oración condicional para hablar acerca de algo que siempre sucede. Es como una ley. En este tipo de condición if (si) tiene un significado similar a when (cuando): If you put water in a cooler, it freezes.(Si colocas agua en el congelador, ésta se congela) (= When you put water in a cooler, it freezes)(Cuando colocas agua en el congelador, ésta se congela) If you heat ice, it melts.(Si calientas hielo, éste se derrite) (= When you heat ice, it melts)(Cuando calientas hielo, éste se derrite)

CLAUSULA CONDICIONAL IF + present simple CLAUSULA PRINCIPAL WILL / 'LL / WON'T + infinitive

En cambio, se utiliza esta segunda alternativa de oración condicional para hablar acerca de un probable resultado futuro, es decir, que no es absolutamente seguro: If I wear the green jacket, it'll go with my new shoes. (Si uso la chaqueta verde, ésta hará juego con mis zapatos nuevos) If you don't study, you won't pass the FCE exam.(Si no estudias, no aprobarás el examen de First Certificate) >> ;-( En estas oraciones condicionales generalmente podemos utilizar unless (a menos que) en lugar de la estructura if... not (si... no). Observa: Unless you study, you won't pass the exam.(A menos que estudies, no aprobarás el examen de First Certificate) (= If you don't study, you won't pass the exam)(= Si no estudias, no aprobarás el examen) Unless I wear clothes like theirs, my friends will think I'm a bit strange.(A menos que use el mismo tipo de ropa que ellos, mis amigos pensarán que soy algo raro/a) (= If I don't wear clothes like theirs, my friends will think I'm a bit strange)(Si no uso el mismo tipo de ropa que ellos, mis compañeros pensarán que soy algo raro/a) Los ejemplos que has analizado arriba muestran dos patrones diferentes para esta case de condiciones. Sin embargo, son posibles también otras combinaciones de formas verbales. Aquí tienes dos ejemplos: If you get the chance, visit Buenos Aires in spring.(Si tienes la oportunidad, visita Buenos Aires en primavera) If you're not nervous, why is your hand shaking?(Si no estás nervioso/a, ¿por qué está temblando tu mano?) Las combinaciones posibles pueden llevar incluso verbos modales como en estos tres ejemplos. If you have finished, you may go. >> MODAL VERB: may (Si has terminado, puedes irte) If you're feeling ill, you ought to see a doctor. >> MODAL VERB: ought to (Si te estás sintiendo mal, deberías ver a un médico) If Mirta, Ricardo and Miguel could do those webs, they can do anything.>> MODAL VERBS: could (past) - can (present) (Si Mirta, Ricardo y Miguel pudieron hacer esas webs, pueden hacer cualquier cosa). conditional type 0 >> ZERO CONDITIONAL IF + SIMPLE PRESENT + SIMPLE PRESENT Used for scientific facts or general truths (usado para expresar verdades científicas, hechos que nunca cambian o situaciones que siempre ocurren). Algunos gramáticos incluyen este tipo de condicional dentro de FIRST CONDITIONAL o Conditional Type I. If you heat butter, it melts. Si calientas manteca, ésta se derrite. If you put water in a cooler, it freezes. Si colocas agua en el congelador, ésta se congela. If you heat water to 100 degrees, it boils. Si calientas agua a 100 grados, ésta hierve. If you cross an international date line, the time changes. Si cruzas una línea de tiempo internacional, la hora cambia. If you drop ice in water, it floats. Si tiras hielo al agua, éste flota. If iron gets wet, it rusts. Si el hierro se moja, se oxida. conditional type I >> FIRST CONDITIONAL Used to talk about things which are possible in the present or the future. It is generally used for things which may happen (utilizado para cosas que pueden ocurrir en presente o futuro). a) IF + SIMPLE PRESENT + SIMPLE FUTURE If you study hard, you will pass your exams. Si estudias intensamente aprobarás tus exámenes. If we do not protect the panda bears, they will soon become extinct. Si no protegemos a los osos panda, pronto se extinguirán. b) IMPERATIVE + OR / AND + SIMPLE FUTUREUsed for threats and promises (usado para expresar amenazas y promesas) Don't say a word about this, or I will kill you. No cuentes una palabra de esto o te mato. Finish your job, and you will have a bonus. Termina tu tarea y tendrás una gratificación. c) IMPERATIVO + IF / IN CASE + SIMPLE PRESENT Contact me if you need any help. Ponte en contacto conmigo si necesitas ayuda. Call them in case you need help. Llámalos en caso de necesitar ayuda. NOTE: In cases b and d above, you can replace IF (si) by UNLESS (a menos que) conditional type II >> SECOND CONDITIONAL Used to talk about things which are unreal (not true or not possible) in the present or the future. It is generally used for things which don't or won't happen. It is generally used for things which may happen (utilizado en presente o futuro para expresar situaciones hipotéticas, que normalmente son irreales o imposibles). IF + SIMPLE PAST + SIMPLE CONDITIONAL If FIRST verb in the sentence is TO BE, WERE is used for all persons. (Si el PRIMER verbo de la oración es TO BE, se usa WERE para todas las personas) If I were rich, I would buy a castle. Si fuera rico, compraría un castillo. If I were him, I would go and see a doctor. Si fuera él -en su lugar- consultaría con un médico. If elephants had wings, they would be able to fly. Si los elefantes tuvieran alas, podrían volar. NOTE: You can replace IF (si) by UNLESS (a menos que) in the examples above. conditional type III >> THIRD CONDITIONAL Used to talk about unreal situations in the past, that is, things which did not happen in the past. (utilizado para expresar situaciones irreales – que nunca sucedieron – en el pasado y, en general, dentro de un contexto de crítica, queja o remordimiento). En español tienes una construcción similar por lo cual este condicional no debería resultar complicado. IF + PAST PERFECT + CONDITIONAL PERFECT If FIRST verb in the sentence is TO BE, WERE is used for all persons. (Si el PRIMER verbo de la oración es TO BE, se usa WERE para todas las personas) If I had known that you were sick, I would have gone to see you. Si hubiese sabido que estabas enfermo, te habría ido a ver. The real situation was that I didn't know you were sick. So I say If I had known... When you are talking about the past, you use the Past Perfect (I had known) after IF. If you had saved your money, you could have bought a laptop. Si hubieses ahorrado tu dinero, podrías haberte comprado una computadora. The real situation was that you didn't save your money. So they say If you had saved... When you are talking about the past, you use the Past Perfect (I had known) after IF. If you hadn't been late for work so often, they wouldn't have fired you. Si no hubieses llegado tarde al trabajo tan seguido, no te habrían despedido. The real situation was that you wasn't early for work. So they say If you hadn't been late... When you are talking about the past, you use the Past Perfect (I had known) after IF. NOTE: You can replace IF (si) by UNLESS (a menos que) in the examples above.