Conditional Sentence adalah kalimat pengandaian.Conditional terbagi atas 4 bagian, yaitu :
• Factual Conditional (Type 0)
To talk about general Truth. (Untuk menyatakan sesuatu yang umum terjadi dalam suatu situasi dan yang merupakan hubungan sebab – akibat).
POLA :
If + Simple Present + Simple Present
Example :
1. If you mix yellow and blue, you get green.
2. If you eat to much, you gain weight.
3. If the temperature of water drops to freezing point, it turns into ice.
4. If water is added to oil, the oil floats on top.

• Open Conditional (First Conditional = Type 1)
To talk about things in the future which can happen or which are possible. (untuk menyatakan sesuatu yang mungkin terjadi di waktu yang akan datang)
POLA :
If + Simple Present + Simple Future
Example :
1. If it rains, he will stay at home.
2. I will tell you what he said, if you don’t tell anyone.
3. If I finish my work early today, I will go to the movie.
4. If you leave before six, you will catch the bus.
5. I will explain the lesson if you ask me.
6. If you submit your home work , you will get a good grate.
7. If you give me money, I will help you.
8. If you help me, I will give you money.
9. If you leave your sister alone, she will miss you.

Improbable Conditional (Type 2)

To talk about unreal present or future situations. (untuk menyatakan sesuatu yang tidak mungkin terjadi / kemungkinan terjadinya kecil).
POLA :
If + Simple Past + Past Future
Example :
1. If I were a bird, I would fly. (the fact : I’m not a bird)
2. If I knew the answer, I would tell you. (the fact : I don’t know the answer)
3. If she knew your number, she would call you. (the fact : she doesn’t know your number)
4. If he went to bed earlier, he would not be so tired in the morning. (the fact : he doesn’t go to bed earlier)
5. If I were you, I would be very angry. (the fact: I’m not you, so I’m not very angry).

Imposible Conditional (Type 3)

To talk about unreal past situations. (untuk menyatakan suatu kejadian yang terjadi di masa lampau).
POLA :
If + Past Perfect +Past Future Perfect
Example :
1. If it hadn’t rained yesterday, I would have gone to the beach. (the fact : it rained yesterday, so I didn’t go to the beach)
2. If I had had more time, I would have helped her. (the fact : I didn’t have more time, so I didn’t help her)
3. If I had seen you, I would have said hello. (the fact : I am sorry, I didn’t see you)
4. If her grandfather had been immediately taken to the hospital, he would have been saved. (the fact: Her grandfather didn’t immediately taken to the hospital, so he didn’t save)
5. If Jono had studied hard, he would have passed the exam. (the fact: Jono didn’t study hard, so he didn’t pass the exam)

Lyrics:
If you wanna get the special lovin ’here’s a view things you’ll need to know if you want to be. (Dear Future Husband – Meghan Trainor) Conditional Sentence Type 1
If you leave me now You’ll take away the biggest part of me.Ooh….no baby please don’t go. (If you Leave Me Now – Chicago) Conditional Sentence Type 2

If I were you holding the world right in my hands the first thing i’d dois thank the stars for all that I have if I were you. ( If I Were You – Hoobastank) Conditional Sentence Type 3

Sumber:
http://www.materibahasainggris.com/penjelasan-dan-contoh-conditional-sentences-type-1-2-3/
http://www.ef.com/english-resources/english-grammar/conditional/
https://www.grammarly.com/blog/conditional-sentences/