1. Future possible
If + v ( Present ) , subj + will
+ infinitive หรือ - subj + will
+ infinitive , + if + V (Present)
ถ้ามี should ให้ขึ้นต้นประโยค
- If he studies hard , he will succeed , หรือ
- He will succeed if he studies hard.
- If she telephones, tell me at once. หรือ
- Should she telephone, tell me at once.
2. Present unreal
If +V (subj. + past)
, would + infinitive
(v.to be ใช้ were ทุกพจน์ )
หรือ ตัด if ใช้ were
- If I were rich, I would buy a new car.
(but I’m not rich) หรือ
- Where I rich, I would buy a new car. หรือ
- I would buy a new car if I were rich.
3. Past unreal
If + V (past perfect)
คือ had + V3, subj + would
Have + V3 หรือตัด If ออกใช้
Had + subj + V3 หรือ Subj.
Would have + V3 + If + had + V3
- If she had been there, she would have
seen the accident (but she was not there)
- Had she been there, she would have
Seen the accident. หรือ
- She would have seen the accident if
she had been there.
request advise order insist
purpose demand prefer ask
require move urge suggest
subj. + v + that + subj. + (should) + infinitive without to
Ex. She insisted that I (should) be here at seven o’clock
I suggested that she (should) come early.
The doctor advised that the patient be rest.
- It is necessary, important
- It is essential, imperative that
- It is advisable, better
- It is (my, his, etc.) wish that
Ex. It is necessary that they (should) work harder.
It is better that we (should) take the examination
It is my wish that he (should) take her out to dinner.
It is her wish that you (should) do that work.
Present subjunctive Past perfect subjunctive
wishif as if
It’s about time
It’s high time
- past subjunctive กริยาคำหลังเหล่านี้ใช้ past tense (ไม่เป็นจริงในปัจจุบัน)
Ex. I wish I were a millionaire. (but I’m not)
If only he come. (but he doesn’t
It’s about time the class began. (but it doesn’t)
- past perfect subjunctive กริยาหลังคำเหล่านี้ใช้ past perfect (ไม่เป็นจริงในอดีต)
Ex. It is time the students had had breakfast. (but they didn’t)
Supposing we had finished our homework (but we didn’t)