1. Conditionals

2. Zero Conditionals
The zero conditional is a structure used to talk about general truths - things which always happen under certain conditions.

3. The structure of a zero conditional sentence
A zero conditional sentence consists of two clauses, an "if" clause and a main clause
If clause+ main clause:
If you heat water to 100 degrees, it boils.

4. If the "if" clause comes first, a comma is usually used.
if clause: if +subject + present simple
main clause: subject + present simple
Water boils if you heat it to 100 degrees.

5. Let’s Practice:
Use the conditions and results in the box to complete the phrases below.
Conditions: you've got a headache, you don't wear a crash helmet, you heat it to 100 ºc, she comes home very late, you leave gates open in the country, you add sugar
Results: you get pink, A dog bites, the DVD player comes on, Butter melts, it scratches you, You have more chance of being killed
Water boils if __________________________________
If you mix red and white _________________________________
____________________________________ if you leave it in the sun.
If ____________________________________ , take an aspirin.
If _____________________________________ , it tastes sweet.
__________________________ if you go near its food when it's eating.
If you pull a cat's tail, _______________________________ .
_______________if you don't wear a seat belt.
You can end up brain damaged if ______________________________
If you press this switch, ____________________________________
If ____________________________________ , her folks get very angry.
Farmers get very angry if _______________________________________

6. The First Conditional
The first conditional (also called conditional type 1) is a structure used to talk about possibilities in the present or in the future

7. The structure of a first conditional sentence
A first conditional sentence consists of two clauses, an "if" clause and a main clause:
if clause main clause
If you study hard , you will pass the test.

8. if clause: if + subject + present simple
main clause: subject + future simple (will)/ imperative/can.

9. If you leave now,you will arrive in time
( future simple )
If you are hungry, eat something
(imperative)
If you need help, you can ask the teacher .(can) (

10. Let’s Practice:
If Clare ________   late again, the hockey trainer will be furious. (to arrive)
You'll be sorry if you ___________________  for your exams. (to revise)
We ___________________  if the weather's good. (to go)
They _____________  you if you wear a wig and dark glasses. (to recognize)
If the bus ________________ on time, I won't miss the football. (to be)
If you ____________ your homework now, you'll be free all tomorrow. (to do)
We___________________  out if there's no food at home. (to eat)
You'll find life much easier if you ____________ more often. (to smile)
If it's hot, we___________________  for a swim. (to go)
You'll do it better if you ___________________ more time over it. (to take)
If she ___________________ practicing, she'll get better. (to keep)
I___________________  so happy if I pass the exam. (to be)
You'll be really tired tomorrow if you ___________________  to bed soon. (to go)

11. Second Conditional
The second conditional (also called conditional type 2) is a structure used to talk about unreal situations in the present or in the future .

12. If clause main clause
If I had a million dollars , I would buy a mansion

13. We use different verb forms in each part of a second conditional:
if clause: if + subject + simple past
main clause: subject + would + verb
+could + verb
+ might +verb
Note that this "simple past" form is slightly different from usual in the case of the verb BE. Whatever the subject, the verb form is "were", not "was": If I were rich, I'd buy a big house.

14. Let’s Practice:
If Joe……….. (be) here, he …………(catch) some fish for supper. 2. It …………(be) nice if the rain………… (stop)! 3. I ………….(sing) you a song if I ……..(have) my guitar. 4. If I …………(have) a better sleeping bag, I………. (not feel) so cold. 5. If this tent….. (be) smaller, one of us ..(have to sleep) outside!
6. I ………………………(go ) to the doctor if I………( be) you. 7. If I ………(not be) so hungry, I (share)…… my beans with you.

15. Third Conditional
The third conditional (also called conditional type 3) is a structure used to talk about unreal situations in the past.

16. If I had studied harder, I would have passed the exam.
If clause main clause
If I had studied harder, I would have passed the exam.
Explanation:
I failed the exam, because I didn't study hard enough.

17. if clause: if + subject + past perfect
main clause :subject + would / could,/ might +have + past participle
*The past perfect is formed with the auxiliary verb "had", and the past participle (or third form) of the verb.
had been( hubiera sido o estado )/ had studied( hubiera estudiado)
*The perfect conditional is formed with would+have+ past participle
Would have been( habría sido) would have arrived( habría llegado)

18. The third conditional is used to talk about things which DID NOT HAPPEN in the past.
If you had driven more carefully, you would not have had an accident.
( You had an accident because you didn't drive carefully enough)

19. Let’s Practice:
1.He crashed his car, because he fell asleep while driving. If he ……………asleep while driving, he……………….. his car. 2. We couldn't go to the concert, because we didn't have enough money. If we……………. enough money, we…………….. to the concert. 3. I lost my job because I was late for work. I……………………. my job if I………………. late for work. 4. The wind was so strong that the bridge collapsed. If the wind ………………so strong, the bridge…………………… I couldn't call Sally because I had lost her number. I …………………..Sally if I…………………… her number.

20. Unless ( if………..not) OTHER WAYS OF SAYING IF
I´ll take the job unless the pay is too low.
I´ll take the job if the pay isn´t too low.
Unless you leave now,you will miss the train
You will miss the train if you don´t leave now

21. Suppose /supposing As long as/so long as
Suppose/supposing he comes tomorrow,
will you meet him?
As long as/so long as
You can go out tonight,as/so long as you come back by midnight

22. On (the) condition that
She agreed to come on (the) condition that she could bring her dog.
Provided/providing that
He could have recovered provided that he had followed the doctor´s orders

23. In case Otherwise Take an umbrella in case it rains. In case of + noun
In case of accident,notify the police
Otherwise
You´d better hurry.Otherwise,you´ll be late for your appointment