Conditional sentences

Conditional sentences (If clauses)
Open / true / real condition (type 1)
Eg; If I have time, I shall visit you.
John usually walks to school if he has enough time.
If you meet her, please tell her about that.
Unreal in present (type 2)
Eg; I don’t have money. If I had much money, I would buy a new house.
I would not tell him about that if I were you.
If she practiced English every day, she could speak it fluently.
Unreal in the past (type 3)
Eg; If yesterday had been a holiday, I would have gone to the movies.
You might have killed the child if you hadn’t stopped your car in time.
If he had driven more carefully, he could have had fewer accidents.
* Condition in the past, the result in present
Eg; If I had studied better, now I could find a job.
He would see her if he had believed her.
CONDITION
IF CLAUSE
MAIN CLAUSE

- TYPE 1
- Simple Present
(S + Vo / Vs-es )
don’t / doesn’t + Vo
- Will / Shall / Can / May … + Vo.
- Simple Present ( the truth)
- Vo … (Imperative Mood)

- TYPE 2
- Past subjunctive
(S + Were / V2ed )
- Would / Should / Could / Might … + Vo.

- TYPE 3
- past perfect subjunctive
(S + had + V3ed )
- Would / Should / Could / Might … + have + V3ed .

- TYPE 4
- past perfect subjunctive
(S + had + V3ed )
- Would / Should / Could / Might … + Vo.

Notes:
Unless = If … not: (nếu … không, trừ phi)
Eg; If you don’t study hard, you’ll fail in the exam.
= Unless you study hard, you’ll fail in the exam.
If she doesn’t water the flowers, they will die.
= Unless she waters the flowers, they will die.
If I have time, I will help you.
= Unless I have time, I won’t help you.
If we had more rain, our crops would grow faster.
= Unless we had more rain, our crops wouldn’t grow faster.
If I won a big prize in a lottery, I’d build a school for the poor.
= Unless I won a big prize in a lottery, I wouldn’t build a school for the poor.
- IF CLAUSE (UNLESS
+ Thể phủ định ( khẳng định (mệnh đề chính không đổi).
+ Thể khẳng định ( khẳng định (đổi động từ trong mệnh đề chính sang thể ngược lại).
If, Unless không cần sử dụng trong câu điều kiện:
Eg; If they were stronger, they could lift the table.
= Were they stronger, they could lift the table.
If he had studied hard, he would have passed his exam.
= Had he studied hard, he would have passed his exam.
Exercise 1: Give the correct tense of verbs.
If you (go) away, please write to me.
If you (be) in, I should have given it to you.
He will be sick if he (eat) another cake.
If men (be) more reasonable, there would be no more wars.
If it is convenient, let’s (meet) at nine o’clock.
I (not do) that if I (be) you.
It will be impossible for me to finish my work if you (not cease) this chatter.
If he (take) my advice, everything can go well.
I would have come sooner if I (know) you were here.
He never does his homework. If he (do) his homework, he (not worry) about his exam.
It’s too bad that we lost the game. If you (play) for us, we (win).
What you (do) if she refuses your invitation?
If today (be) Sunday, we (go) to the beach.
They (make) fewer mistakes if they were more careful.
Unless they (pass) their examinations, they would join the army.
I wish I (see) that film on television again.
I wish they (know) the truth yesterday.
If only she (be) our teacher of English.
If I see him, I (give) him a lift.
If I had a typewriter, I (not type) it myself.
Miss Snow (type) ten letters before lunchtime yesterday.
I wish our team (play) better next time.