Conditional sentences contain two clauses: a condition clause introduced by "if" and a consequence clause. There are three types of conditional sentences: type 1 for probable conditions using present tense, type 2 for improbable conditions using past tense, and type 3 for impossible conditions using past perfect. Variations include mixed conditionals combining clause types and substitute words like "unless" or "provided."

2. Conditional Sentences
Composed by 2 clauses
one that expresses the condition: introduced
by the word “if”, commonly known as “if
clause”.
one that expresses the consequence.
Example: If you work hard, you will succeed.

3. Conditional Sentences
There are 3 main types of conditional
sentences:
Type 1 : probable condition
Type 2 : improbable condition
Type 3 : impossible condition

4. Type 1 : Probable Condition
Used for actions which are true or likely to happen
Examples:
If it rains tomorrow, we shall cancel the picnic.
You will be tired if you do a lot of exercises.
• Note on type 1:
If + present tense, future tense

5. Type 2 : Improbable Condition
Used for present or future activities which are
improbable or unlikely to happen
Examples:
If it rained tomorrow, we should stay at home.
You could start dinner if it were ready.
• Note on type 2:
if + past tense, would/should/might + infinitive

6. Type 3 : Impossible Condition
Used for impossible activities which could NOT
be true or performed
Examples:
If it had rained yesterday, I would have stayed at
home.
What would you have done if you had been
attacked by a monster?
• Note on type 3:
if + past perfect, would/should/might + perfect
infinitive

7. Variations
 Mixed conditional sentences. We can form mixed
conditionals, if the context permits it, by combining an if-
clause from one type with a main clause from another.
IF-CLAUSE (type 2) + MAIN CLAUSE (type 1): If she got back
late last night, she won’t come to work today.
IF-CLAUSE (type 2) + MAIN CLAUSE (type 3) : If you were
more sensible, you wouldn’t have spoken to your boss like that.
IF-CLAUSE (type 3) + MAIN CLAUSE (type 2): If she hadn’t
missed the bus, she would be here now.
 Substitute words. We can form conditionals by using
words/expressions such as unless, so/as long as,
provided/providing, suppose/supposing: Unless you arrive
on time you will miss the train; provided/as long as you
arrive on time you won’t miss the train.

8. Summary
Conditional sentences are composed by 2 clauses
 one that expresses the condition
 one that expresses the consequence
3 main types of conditional sentences.
 Type 1 : Probable Condition
 Type 2 : Improbable Condition
 Type 3 : Impossible Condition
Variations
- Mixed conditionals
- Substitute words: unless, so/as long as, provided/providing,
suppose/supposing.