‘If’ clauses are also called 'Conditional Clauses'.
There are three types of ‘If’ clauses. They are:
Type 1 : It is possible and very likely the condition will be fulfilled
( Simple Present + will/can/may )
Examples:
If you bring your notebook, we can complete the project work.
If Yamini takes the tablets, the fever will go.
If there is less pollution, we may see good rains.
Type 2 : It is possible but very unlikely the condition will be fulfilled
( Simple Past + would/could/might )
Examples:
If they found him, they would give him your mobile number.
If Kavya brought apples here, he could eat them.
If they met him, they might tell him the story.
We, sometimes, use Type 2 in hypothetical situations
If I were PM, I would provide everyone with free education and free health.
Type 3 : It is impossible that the condition will be met because it talks about the past
( Past Perfect + would/could/might + have + V3 )
Examples:
If had gone there, I would have talked to him.
If Gomati had seen him, she might have requested his help.
If Karunya had taken the medication, she could have escaped the hospitalization.
(Note: There are many exceptions to the above rules, which we may discuss somewhere else)
Practice Bits
Fill in the following blanks with appropriate forms of the verbs that are given in brackets.
1. Uma _______ (bring) apples if she goes to the market.
2. If he had seen her, he _______ (give) her my contact number.
3. If Mohan applied for leave, the HM ______ (reject) it.
4. If the Government of India allows, TATAs ______ (buy) the company.
5. If Naveen had taken right medicine, he ________ (recover) from the disease.