If Clause 3 แบบ (Conditional Statement)

รูปแบบของ If-Clause มีทั้งหมด 3 ประเภท

There are four different types of conditional sentences in English. 

Meaning

type	if-clause	ความหมาย
0	General truths	ใช้กับเหตุการณ์ที่เป็นความจริง
I	A possible condition and its probable result	ใช้กับเหตุการณ์ที่เป็นเหตุเป็นผลซึ่งกันและกัน
II	A hypothetical condition and its probable result	ใช้กับเหตุการณ์ที่ตรงข้ามความจริงในปัจจุบัน หรือ อนาคต
III	An unreal past condition and its probable result in the past	ใช้กับเหตุการณ์ที่ตรงข้ามความจริงในอดีต

Form

type	if-clause	main clause
0	Simple Present If S + v.1	Simple Present S + v.1
I	Simple Present If S + v.1	will-future or (Modal + infinitive) S + will + v.infinitive
II	Simple Past If S + v.2	would + infinitive * S + would + v.infinitive
III	Past Perfect If S + had + v.3	would + have + past participle * S + would + have + v.3

Example

type		Examples
		long forms	short/contracted forms
0		If you do not brush your teeth, you get cavities.	If you don’t brush your teeth, you get cavities.
		If people eat too much, they get fat.	If people eat too much, they get fat.
		If babies are hungry, they cry.	If babies are hungry, they cry.
		People die if they do not eat.	People die if they don’t eat.
I	+	If I study, I will pass the exam.	If I study, I'll pass the exam.
	-	If I study, I will not fail the exam. If I do not study, I will fail the exam.	If I study, I won't fail the exam. If I don't study, I'll fail the exam.
II	+	If I studied, I would pass the exam.	If I studied, I'd pass the exam.
	-	If I studied, I would not fail the exam. If I did not study, I would fail the exam.	If I studied, I wouldn't fail the exam. If I didn't study, I'd fail the exam.
III	+	If I had studied, I would have passed the exam.	If I'd studied, I'd have passed the exam.
	-	If I had studied, I would not have failed the exam. If I had not studied, I would have failed the exam.	If I'd studied, I wouldn't have failed the exam. If I hadn't studied, I'd have failed the exam.