Conditional sentences have two clauses: an if-clause and a main clause. There are different types of conditional sentences depending on the tenses used. A zero conditional uses present tense in both clauses to describe universal truths or scientific facts. A first conditional uses a present tense if-clause and a future tense main clause to talk about possible future events, make promises, or give warnings.

1. Conditional
Sentences

5. Conditional Sentences
Structure :
A conditional sentence is composed of 2
parts :
If-clause + Main Clause
Example :
If it rains tomorrow, we will not come.
If-clause Main Clause

6. Conditional Sentences
Types :
 The order of the two clauses is
flexible, it’s not
important.
But if the if-clause comes first, it
must be followed by
a comma.
If it rains, I’ll stay at home

7. • Zero Conditional:
present simple/present simple
• Water boils if it reaches 100º
• First Conditional:
present simple/ future
• If I study, I’ll pass
Conditional Sentences

8. Zero Conditionals
Tense : Present tense in both clauses
Example
:
If you heat water to 100°C, it boils.
If you pour oil into water, it floats.
Present Tense Present Tense

9. Zero Conditionals
Use :
 Talk about universal truth.
If you heat ice, it turns to water
To give commands
If you are tired, go to bed!

10. Zero Conditional
General Truths:
If condition result
If it rains, we get wet.
Scientific Facts:
If condition result
If the water boils, it is not cold

11. Zero Conditional
Things that always happen under certain
Conditions:
If condition result
If I study, I get good marks

13. THE FIRST CONDITIONAL
• If Alice works hard ,she will pass the exam
• If you go to Rome, you might visit the Coliseum
• If you need my help, call me ¡

14. MATCH
• If you use drugs
• If I get bored in class
• If that company fails
• If you get in trouble
• If he loves that girl
• …I will assist my
partners
• … I will punish you
• … he might talk to
her
• … you will be sorry
sooner or later
• … workers will lose
their jobs

15. COMPLETE the sentences
• If you ……..(go) to see this film, you will have a good time
• If she …….(play) sports , she will live longer
• She …….(not be) an architect if she doesn`t go to university
• We ……. ( get) a 7 if we finish the exercises

16. Write sentences
• The weather/be good - go / the beach
• Go/to school on foot - be / late
• Have / money - buy / present
• Do/ homework - find / notebook
• Mum / give $20.000 - wash / windows

17. First Conditionals
Tense :
If-clause ~ Present Tense
Main Clause ~ Future Tense
If I feel sick tomorrow, I will not go to school.
If it rains, the match will be cancelled.
Present Tense Future Tense

18. First Conditionals
Use :
 To speak about possible or probable
future events.
If the weather is sunny tomorrow, we will go surfing.
To make promises or warnings
If you forget my birthday, I’ll never speak to you
again.
 Unless is used in negative conditionals
Unless we recycle more, we won’t have a better
world.