There are 3 types of conditional sentence:
Pattern:
If + S + V1/Ves/Vs + O , S + {will, shall} + V1 + O
Example:
If I have much money, I will go to Mecca.
The fact: I'm still have no much money, but later maybe (possesibility happenened)
NOTE: - The first type use VERB 1.
- The sentence before comma is Present Tense, and the sentence after comma is future tense.
- The condition is possesibility happened.
Pattern:
If + S + V2 + O, S {would, should} + V1 + O
Example:
If she went to Bali, she would buy some souvenirs for me.
The fact: She doesn't go to Bali, so she doesn't buy me any souvenirs.
She isn't in Bali now.
NOTE: - The second type use VERB 2.
- The sentence before comma is Past Tense, and the sentence after comma is future tense with past modals.
- The condition happened at present.
Pattern:
If + S + V3 + O, S + {WOULD, SHOULD} + HAVE + V3 + O
Example:
If he had a new job in London, he would have bought a new house
The fact: He didn't get a new job in London, so he did't buy a new house.
NOTE: - The third type VERB 3.
- The sentence before comma is Present Perfect, and the sentence after comma is Past Perfect.
- The condition happened at the past.
All the sentence before comma can remove after comma and the opposite.