Used for general truths and facts. Structure: If + present simple, present simple. Example: If you heat water to 100 degrees, it boils.
Used for real and possible situations in the future. Structure: If + present simple, will + base form. Example: If it rains, I will stay at home.
Used for unreal or unlikely situations in the present or future. Structure: If + past simple, would + base form. Example: If I won the lottery, I would travel the world.
Used for unreal situations in the past. Structure: If + past perfect, would have + past participle. Example: If he had studied harder, he would have passed the exam.
Combines elements of different conditional types. Example: If I had known, I wouldn't be here now.
Mastery of conditional sentences enables you to express various possibilities and scenarios in English.