1. Conditionals

3. Four basic forms:
Zero conditional If + present tense – present tense First conditional If + present tense – will (not) + infinitive Second conditional If + past tense – would (not) + infinitive Third conditional If + past perfect – would (not) have + past participle
The “if-clause” is the Adverbial Clause of Condition.

4. If + present simple present simple
Zero conditional
If + present simple present simple
Occurs at any time, and often more than once (General conditional). Also for scientific facts.
In these sentences if can usually be replaced by when.
If means it is uncertain or hypothetical
When means that is certain or definite
If she drinks cola, she burps. (It’s uncertain that she still drinks cola.)
When she drinks cola, she burps. (This happens every time she drinks.)
Extra practice:

5. Zero conditional
If + present simple present simple If you heat water to 100 C, it boils. If you press this key, the computer shuts down. If your pupils are unruly, they are probably bored. If you want to learn, you have to study.

6. Zero conditional other uses
To give instructions or commands:
If + present simple imperative
If a strange dog starts to bark at you, stand very still.
If the boat sinks, get into a lifeboat quickly.
More on the Zero Conditional and exercises:

7. First Conditional
If + present simple will / won’t + infinitive This conditional is used when something is likely or possible.

8. If I get a bad grade, my father will get angry.

9. First Conditional If he gets angry, he won’t give me money.
If I don’t have money, I won’t go out.
If I don’t go out, I won’t see my girlfriend.
If I don’t see her, she ’ll break up with me.
First Conditional

10. First Conditional
If these lessons become more expensive, a lot of people will not (are not going to) be able to do them. People will not come to see the play if you don’t advertise for it. If dad gets a promotion, we ’ll go on holiday!

11. First conditional
With modals: If you can finish this chapter tonight, you may be able to finish the whole book tomorrow. If he comes back it might be a good idea to tell him about it.
…but no “will” or “would” in the if-clause!

12. First conditional  other uses
Offers: I ’ll book a table for us if you don’t have time. Suggestions: Shall I buy a present if the shop is still open? Warnings: You ’ll have to pay for it if you damage someone else’s property.

13. If + past simple would (not) + infinitive
Second Conditional
If + past simple would (not) + infinitive
Improbable future events or situations
If they had a house in France, they would go there every weekend.
Hypothetical current situations or events
If she thought there was a good chance of winning, she would buy lottery tickets every month.
Extra exercises here (scroll down to the Conditionals):

14. Second Conditional
With modals: If you could finish this chapter tonight, you might be able to finish the whole book tomorrow. If he came back it might be a good idea to tell him about it.
…but no “will” or “would” in the if-clause!
(Adverbial clause of condition)

15. Second conditional  other uses
Giving advice:
If I were you, I would not let her play there.
Polite requests:
If you could bring that along, that would be very handy.
Desires / regrets:
If it didn’t cost so much, we could buy that new game.
Second Conditional Sentences in The Big Bang Theory

16. If + past perfect -- would (not) have + past participle
Third Conditional
If + past perfect -- would (not) have + past participle
Hypothetical situations or events in the past
(= an unreal or impossible situation).
If the bus had come on time, we wouldn’t have been late for class.

17. Third Conditional With modals:
If you had finished this chapter tonight, you might have been able to finish the whole book tomorrow.
If he had come back, it might have been a good idea to tell him about it.
…but no “will” or “would” in the if-clause!
(Adverbial clause of condition)

18. Third conditional  other uses
To express criticism:
If you hadn’t been drinking so much, you would have noticed that expensive statue on their lawn!
Extra exercises on Conditionals I, II, and 111

19. Mixed Conditionals These include forms from different patterns:
Mixed 2nd and 3rd:
If Australia weren’t flooded, most people wouldn’t have heard of Brisbane.
( A hypothetical situation or event in the present, while the result in the main clause refers to the past)
Australia is still flooded NOW, but most people have heard of Brisbane in the past two weeks.

20. Mixed Conditionals These include forms from different patterns:
Mixed 3rd and 2nd:
If he had left his millions to his mistress, that would cause some gossip!
(A hypothetical situation or event in the past, while the result in the main clause refers to the present )

21. Alternatives
Alternatives to if: Unless Provided that ... On the condition that ... See pgs.123 / 124 ALG So long as .... (as long as...) But for ... Suppose ... What if ... In case ... Even if ... Whether ....
…but no “will” or “would” in the Adverbial clause of condition!

22. If he would lend me thirty pounds, I could buy the tickets.
A mnemonic for
no “will” or “would” in the Adverbial clause of condition:
If with will or would
Is never any good!
The most common Ped.Grammar 1 error regarding conditionals is the use of “will” or “would” in an Adverbial Clause of Condition, like this:
If he would lend me thirty pounds, I could buy the tickets.
UNGRAMMATICAL!

23. Which conditional form is used here?

24. On holiday in Paris, a grandmother took her granddaughter to see the most famous works of art in the Louvre Museum. One of the highlights was the beautiful marble statue of the Venus de Milo.
After a few moments of gazing at the statue, the grandmother said, “See, dear? This will happen if you keep biting your fingernails!”