There are three types of conditional statements using "if": 1) Situations that are untrue in the present. 2) Real or possible situations. 3) Situations that are untrue in the past. The structure changes depending on whether the "if" clause refers to a possible present/future situation or an impossible past situation. A contrary-to-fact conditional in the past uses the past perfect tense in the if-clause and "would have" or "could have" in the result clause.

1. 
By : Endangdiah Ayu

2. There are three types of
conditional “if” :
- Untrue in the present
- Real
- Untrue in the past


4. b.
For the example
a.
If I had enough money, I would buy a car.
I would go to the park, If the weather were nice.

5. Situation
If- clause
Result
True
Simple present
Will
form
Can
Contrary-to-fact
Simple past
Would
form
Could
+ simple
+ simple

6. True situation :
a. If you need some money, I { will / can }
lend you some.
 Contrary – to – fact – situation
b. If you needed some money, I { would /
could } lend you some.


7. If – clause : The past perfect
Result clause : would have/could have + past
participle

8. A.
If I had had enough money, I would have bought a car.
B.
If the weather had been nice yesterday, I would have
gone to the park.