By Ajarn Pornwilai Kaewprachan Conditional sentence By Ajarn Pornwilai Kaewprachan

Conditional sentence Conditional sentence หรือ if clause หมายถึง (main clause) ตัวอย่างเช่น If he comes , I will tell him the truth. (main clause) (if-clause) If he comes เป็น if-clause I will tell him the truth เป็น main clause

นักเรียนลองพิจารณาข้อความต่อไปนี้ ข้อความใดเป็น main clause If you want a new dress, you should save your money now. คำตอบ you should save your money now เป็น main clause

นักเรียนลองพิจารณาข้อความต่อไปนี้ ข้อความใดเป็น main clause Somchai won’t come if you don’t write to him. คำตอบ Somchai won’t come เป็น main clause

นักเรียนลองพิจารณาข้อความต่อไปนี้ ข้อความใดเป็น main clause Boil some water if you want some tea. คำตอบ Boil some water เป็น main clause

นักเรียนลองพิจารณาข้อความต่อไปนี้ ข้อความใดเป็น main clause If Sunee is free, she may come. คำตอบ she may come เป็น main clause

ประเภทของ If clause แบ่งเป็น 4 ประเภทตามเหตุการณ์ที่เกิดขึ้น 1. General Truth 2. Future Possible 3. Present Unreal 4. Past Unreal เลือกประเภทที่จะเรียน ทำแบบฝึกหัด

ประเภทของ If clause แบ่งเป็น 4 ประเภทตามเหตุการณ์ที่เกิดขึ้น 1. General Truth 2. Future Possible 3. Present Unreal 4. Past Unreal เลือกประเภทที่จะเรียน ทำแบบฝึกหัด

1. General Truth คือ ประโยคเงื่อนไขที่เป็นจริงและผลที่เกิดขึ้นจะเป็น เช่นนั้นเสมอ จะใช้รูปกริยาดังนี้ If + present simple, present simple หรือ present simple + if + present simple If the sun sets, it sets in the west. ถ้าพระอาทิตย์ตก มันจะตกทางทิศตะวันตก (เป็นเหตุการณ์ ที่เป็นจริง จึงใช้รูปประโยคเป็น Present Simple Tense

The save is open if you press this button. เซฟจะเปิดเมื่อคุณกดปุ่มนี้ (ข้อความนี้เป็นความจริงจึงใช้รูปPresent Simple Tense) I always help her if she asks me. ฉันช่วยหล่อนเสมอเมื่อหล่อนขอร้องฉัน (ข้อความนี้เป็นกิจวัตร จึงใช้รูป Present Simple Tense) If we heat ice, it turns to water. เมื่อเราให้ความร้อนน้ำแข็ง มันจะกลายเป็นน้ำ(ข้อความนี้เป็น ความจริงจึงใช้รูปPresent Simple Tense)

If + present simple, imperative Imperative + if + present simple Ex: If you are in trouble, let me know. Get up if the president comes in. If the teacher asks, answer her. อาจใช้ when หรือ whenever แทน if ได้ Whenever the teacher asks, answer her. The save is open when you press this button.

2. Future possible คือประโยคที่ผู้พูดเชื่อว่าเหตุการณ์น่าจะเกิดอย่างที่สมมติ หรืออาจเป็นไปได้ในอนาคต จะใช้รูปกริยาดังนี้ If + present simple, future simple หรือ Future simple + if + present simple Ex : If you don’t hurry, you may miss the train. I will tell you if he comes. If she calls you, you can go.

3. Present unreal คือประโยคที่แสดงถึงการสมมติอยากจะให้เหตุการณ์นั้น เกิดขึ้นในปัจจุบันแต่ความจริงแล้วไม่ได้เกิดขึ้นใช้รูปกริยาดังนี้ If + past simple, past future simple Past simple + if + past future simple Ex: If he came here now, I could go with you. I would travel around the world if I had a lot of money. If we read the stars, we might know our future.

4. Past Unreal คือประโยคสมมติเรื่องในอดีตซึ่งผ่านไปแล้ว ไม่มีโอกาส เกิดขึ้น จะใช้รูปกริยาดังนี้ If + past perfect , future perfect in the past Future perfect in the past +if + past perfect Ex: If you had stayed up late last night, you might have received his call. If your sister hadn’t helped you, what would you have done?

Conditional sentence สามารถละifได้ Future Possible Ex: If she should telephone, tell me at once. = Should she telephone, tell me at once. If he refuses to come, I will call him. = Should he refuse to come, I will call him.

Conditional sentence สามารถละifได้ Present Unreal Ex: If I were rich, I would buy that car. =Were I rich, I would buy that car. If she saw him, she would speak to him. = Were she to see him, she would speak to him.

Conditional sentence สามารถละifได้ Past Unreal Ex: If you had stayed up late last night, you might have received the call. = Had you stayed up late last night,

สรุป If-clause แบบที่ 1 if + v1. , will + v แบบที่ 2 if + v 2 , would + v แบบที่ 3 if + had + v3 , would have + v3

คำที่ใช้แทน IF provided (that) = ถ้า suppose (that) = สมมุติ If I had known of your arrival, I should have met you. Suppose that I had known of your arrival, I should have met you. Provided I had known of your arrival, I should have met you.

คำที่ใช้แทน IF But for = แต่เพราะ If I do not wear my lifebelt, I should have been drowned. But for my lifebelt, I should have been drowned.

คำที่ใช้แทน IF Unless = ถ้าไม่ นอกจาก Otherwise = ถ้าไม่ หรือมิฉะนั้น No one knows if she doesn’t tell the secret. No one knows unless she tells the secret. No one knows otherwise she tells the secret.

คำที่ใช้แทน IF If only = ถ้าเพียงแต่ Wish = ปรารถนา If he didn’t drive so fast, he wouldn’t lose his leg. If only he didn’t drive so fast, he wouldn’t lose his leg. He wishes he didn’t drive so fast.

Do exercises เลือกแบบฝึกหัด Exercise I Exercise II Exercise III

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Exercise 1/1 If the baby…….,how will you get it back to sleep? a. cries b. is crying c. cried d. had cried

Exercise 1/2 If only it …a fine day, we would go on a picnic. a. was b. were c. had been d. was being

Exercise 1/3 If only I ….you were at home, I would have come. a. did know b. would know c. had known d. knew

Exercise 1/4 If I …..your address, I would write to you. a. would have b. had c. had had d. would have had

Exercise 1/5 …..if Mr. Law had given up the plans? a. What would you do b. What did you do c. What would you have done d. What had you done

Exercise 1/6 ………you in my position, what would you do? a. Unless b. Were c. Had d. If

Exercise 1/7 Supposing no one….! What would you do with all the food you have prepared? a. comes b. came c. had come d. would come

Exercise 1/8 ……if you took off your jacket? a. Won’t you feel better b. Weren’t you feeling better c. Didn’t you feel better d. Wouldn’t you feel better

Exercise 1/9 If you ever…….the Queen, what…. you do? a. will meet, will b. met, will c. meet, would d. met, would

Exercise 1/10 If the employers had been more reasonable, the workers…on strike. a. should not go b. would not have gone c. had not gone d. would not go

Exercise 1/11 If my aunt had not fallen down yesterday,………. a. she can walk normally now b. her legs would not be hunting now c. she does not have to use the support now d. she would not have been painful now

Exercise 1/12 ……..more rain soon, the plants will all die. a. Unless we have b. Unless we didn’t have c. If we have d. If we didn’t have

Exercise 1/13 I …….a bad mistake if I had read the instructions. a. might not have made b. might have made c. may have made d. may not have made

Exercise 1/14 If you finish your homework today, ……… me a visit at 5 p.m. a. give b. gave c. will give d. would give

Exercise 1/15 …..the problems carefully yesterday, you would not be having any difficult now. a. If only you have b. Even if you would study c. If you had studied d. Unless you should study

Exercise 1/16 Should you see him,….him my regards. a. give b. and give c. and will give d. gave

Exercise 1/17 ….to school regularly, he would have learned his lessons well. a. If he went b. Were he to go c. If he would have gone d. Had he gone

Exercise 1/18 ……he would not have been punished. a. If he arrived in time b. If only he had arrived in time c. If he arrived in time only d. If he had arrived in time only

Exercise 1/19 What would happen if the sun ….. tomorrow? a. does not rise b. will not rise c. has not risen d. did not rise

Exercise 1/20 We can’t begin the test ………...the teacher says so. a. when b. unless c. if d. or

Exercise 1/21 If you are so reluctant to help, I ….. the work itself. a. will do b. would do c. had do d. must have do

Exercise 1/22 A: How does Tim behave? B: He behaves as if he……my boss. a. is b. were c. had been d. might be

Exercise 1/23 I should arrive there too late unless I ...the earlier train. a. catch b. caught c. don’t catch d. didn’t catch

Exercise 1/24 If you ….to have tea ready in time, put the kettle on now. a. want b. wanted c. had wanted d. were to want

Exercise 1/25 Had he studied harder, he ….. a. would not have failed b. would not fail c. had not failed d. did not failed

Transition Page

ELEMENTS PAGE

ELEMENTS PAGE

The score คะแนน 20-25 = ดีมาก 13-19 = ดี 0-12 = ปรับปรุง ข้อ 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 ได้ ข้อ 16 17 18 19 20 21 22 23 24 25 รวม ได้ คะแนน 20-25 = ดีมาก 13-19 = ดี 0-12 = ปรับปรุง