Deduction āĻŦা Modal āĻাāĻে āĻŦāϞে? āĻāϤ āĻĒ্āϰāĻাāϰ āĻ āĻি āĻি?
āϝāĻāύ āĻāĻāĻি āĻĒāϰিāϏ্āĻĨিāϤি āϏāĻŽ্āĻĒāϰ্āĻে āĻিāĻু āϏিāĻĻ্āϧাāύ্āϤ āĻ্āϰāĻšāĻŖেāϰ āĻĒ্āϰā§োāĻāύ āĻšā§ āϤāĻāύ Modal verb āĻŦ্āϝāĻŦāĻšৃāϤ āĻšā§। āĻāĻাāύে deduction āĻŦāϞāϤে āĻāĻāĻি āĻĒāϰিāϏ্āĻĨিāϤি āϏāĻŽ্āĻĒāϰ্āĻে āĻĒ্āϰাāĻĒ্āϤ āϤāĻĨ্āϝেāϰ āĻāĻĒāϰ āĻিāϤ্āϤি āĻāϰে āĻোāύ āĻāĻĒāϏংāĻšাāϰে āĻāĻĒāύীāϤ āĻšāĻā§া āĻŦোāĻাā§।
Modal verbs are used where some deduction is needed for a situation. Here deduction means drawing a conclusion about a situation based on the available information.
Types of Modal:
There are three types of modal verbs based on their usage:
- Modal Verbs for Surety
- Modal Verbs for Expectation
- Modal Verbs for Probability
All three types are discussed below.
Modal Verbs for Surety:
1. Surety about the Present:
āϝāĻĻি āĻāĻĒāύি āĻŦāϰ্āϤāĻŽাāύ āϏāĻŽ্āĻĒāϰ্āĻে āĻোāύ āϏিāĻĻ্āϧাāύ্āϤ āĻāĻšāĻŖ āĻāϰেāύ, āĻāĻĒāύাāĻে “must” āĻŦ্āϝāĻŦāĻšাāϰ āĻāϰāϤে āĻšāĻŦে āϝāĻāύ āĻāĻĒāύি āύিāĻļ্āĻিāϤ āϝে āĻোāύāĻিāĻু āϏāϤ্āϝ āĻāĻŦং “can’t” āĻŦ্āϝāĻŦāĻšাāϰ āĻāϰāϤে āĻšāĻŦে āϝāĻāύ āĻāĻĒāύি āύিāĻļ্āĻিāϤ āϝে āĻোāύāĻিāĻু āϏāĻŽ্āĻāĻŦ āύা।
If you make any decision about the present, you have to use “must” when you are sure something is true and have to use “can’t” when you are sure that something is not possible.
Example:
āϝāĻĻি āĻāĻĒāύি āĻāĻāĻāύ Postman-āĻে āĻĻেāĻেāύ uniform āĻĒāϰে āĻŦিāĻিāύ্āύ āĻŦাā§িāϤে āĻিāĻ ি āĻŦিāϞি āĻāϰāĻে, āĻāĻĒāύি āĻŦāϞāϤে āĻĒাāϰেāύ:
- He must be a postman.
āĻāĻŦং āĻāĻāĻāĻাāĻŦে āĻāĻĒāύি āĻŦāϞāϤে āĻĒাāϰেāύ,
- He can’t be a policeman.
2. Surety about the Past:
āϝāĻĻি āĻāĻĒāύি āĻŦāϰ্āϤāĻŽাāύে āĻāĻŽāύ āĻিāĻু āĻĻেāĻেāύ āϝা āĻāĻĒāύাāĻে āĻ āϤীāϤে āĻি āĻāĻেāĻে āϤা āϏāĻŽ্āĻĒāϰ্āĻে āĻāĻāĻি āύিāϰ্āĻĻিāώ্āĻ āĻāĻĒāϏংāĻšাāϰে āĻāĻĒāύীāϤ āĻāϰে, āĻāĻĒāύি “must have”, “must not have” āĻ “couldn’t have” āĻāĻŦং āϤাāϰ āϏাāĻĨে verb-āĻāϰ past participle āϰূāĻĒ āĻŦ্āϝāĻŦāĻšাāϰ āĻāϰāĻŦেāύ।
Can’t have-āĻ āĻŦ্āϝāĻŦāĻšাāϰ āĻāϰা āϝাā§ āĻিāύ্āϤু āĻāĻা couldn’t have-āĻāϰ āϤুāϞāύাā§ āĻুāĻŦāĻ āĻāĻŽ āĻĒ্āϰāĻāϞিāϤ।
If you see such thing at Present which can lead you to draw a certain conclusion about what happened in the Past, you will use “must have”, “must not have” and “couldn’t have” plus the verb’s past participle form.
Can’t have can also be used but it is much less common than couldn’t have.
Example:
āĻāĻĒāύি āϝāĻĻি āĻāĻ āϏিāĻĻ্āϧাāύ্āϤে āĻāĻĒāύীāϤ āĻšāύ āϝে āĻ āϤীāϤে āĻোāύāĻিāĻু āĻāĻেāĻিāϞ, āĻāĻĒāύি āĻŦ্āϝāĻŦāĻšাāϰ āĻāϰāĻŦেāύ-
Must have+ verb-āĻāϰ past participle
- Rima is looking so tired. She must have worked very hard at the office.
āĻāĻĒāύি āϝāĻĻি āĻāĻ āϏিāĻĻ্āϧাāύ্āϤে āĻāĻĒāύীāϤ āĻšāύ āϝে āĻ āϤীāϤে āĻোāύāĻিāĻু āĻāĻেāύি, āĻāĻĒāύি āĻŦ্āϝāĻŦāĻšাāϰ āĻāϰāĻŦেāύ-
Must not have + verb-āĻāϰ past participle
- Namira is absent in the class. She must not have arrived Dhaka yet.
āĻāĻĒāύি āϝāĻĻি āύিāĻļ্āĻিāϤ āĻšāύ āϝে āĻোāύāĻিāĻু āĻ āϏāĻŽ্āĻāĻŦ, āĻāĻĒāύি āĻŦ্āϝāĻŦāĻšাāϰ āĻāϰāĻŦেāύ-
Couldn’t have+ verb-āĻāϰ past participle
- Anika couldn’t have damaged the printer. She was absent in the office yesterday.
Must have āĻāĻŦং couldn’t have-āĻāϰ āĻŦ্āϝāĻŦāĻšাāϰেāϰ āĻĒাāϰ্āĻĨāĻ্āϝ āύিāĻেāϰ āĻāĻĻাāϰāĻŖāĻুāϞো āĻĨেāĻে āĻŦোāĻা āϝাāĻŦে:
- I can’t see him at the meeting. He must not have arrived on time.
(āĻāĻĒāύি āϧাāϰāĻŖা āĻāϰে āύিāĻ্āĻেāύ āϝে āϏে āĻ িāĻ āϏāĻŽā§ে āĻāϏেāύি)
- His flight was delayed for two hours, so he couldn’t have arrived on time.
(āĻāĻĒāύি āĻাāύেāύ āϝে āϤাāϰ āĻĒāĻ্āώে āĻ িāĻ āϏāĻŽā§ে āĻāϏা āĻ āϏāĻŽ্āĻāĻŦ āĻিāϞ)
3. Surety about the Future:
āĻāĻĒāύি āϝāĻĻি āĻāĻŦিāώ্āϝ⧠āϏāĻŽ্āĻĒāϰ্āĻে āĻোāύ āϏিāĻĻ্āϧাāύ্āϤ āύেāύ, āĻāĻা āĻ āύেāĻāĻা āĻāĻŦিāώ্āϝāĻĻ্āĻŦাāύী āĻāϰাāϰ āϏাāĻŽিāϞ। āĻāĻĒāύি āĻাāύেāύ āϝে, āĻāĻĒāύাāĻে “will” or “going to” āĻŦ্āϝāĻŦāĻšাāϰ āĻāϰāϤে āĻšāĻŦে āĻāĻĒāύি āĻāĻŦিāώ্āϝāϤে āϝা āĻāĻāĻŦে āĻŦিāĻļ্āĻŦাāϏ āĻāϰেāύ āϤা āĻĒ্āϰāĻাāĻļ āĻāϰāϤে। āĻāĻĒāύি āϝāĻĻি āĻāĻĒāύাāϰ āĻāĻŦিāώ্āϝāĻĻ্āĻŦাāύীāϰ āĻļুāĻĻ্āϧāϤা āϏāĻŽ্āĻĒāϰ্āĻে āĻĒ্āϰাā§ āϏāĻŽ্āĻĒূāϰ্āĻŖāĻ āύিāĻļ্āĻিāϤ āĻĨাāĻেāύ, āϤāĻŦে āĻāĻĒāύি āϏেāĻ āύিāĻļ্āĻā§āϤা āύিāϰ্āĻĻেāĻļ āĻāϰāϤে “definitely” āĻļāĻŦ্āĻĻāĻি āĻŦ্āϝāĻŦāĻšাāϰ āĻāϰāϤে āĻĒাāϰেāύ।
If you make any decision about the future, it is quite similar to making a prediction. You know that you have to use “will” or “going to” to express what you believe will happen in future. If you are pretty much sure about the correctness of your prediction, you can use the word “definitely” to denote the certainty.
Example:
- Asim is definitely going to love this movie. The movie is full of high-octane action sequences, exactly the type he likes.
- The students will definitely be thrilled when they will come to know that they are going for a picnic to Chittagong.
āĻāĻĒāύি āĻāĻĒāύাāϰ āĻāĻŦিāώ্āϝāĻĻ্āĻŦাāύীāϰ āύিāĻļ্āĻā§āϤা āĻāϰāĻ āύিā§āĻŽāύিāώ্āĻ āĻাāĻŦে āĻĒ্āϰāĻাāĻļ āĻāϰāϤে āĻĒাāϰেāύ is/are certain to āĻŦা is/are sure to āĻŦ্āϝāĻŦāĻšাāϰেāϰ āĻŽাāϧ্āϝāĻŽে।
You can express the certainty of your prediction more formally by using either is/are certain to or is/are sure to.
Example:
- All types of readers are certain to like this book because it is written in an easy and descriptive language.
- The MBA’s are sure to attend this program because it is full of opportunities for them.
Modal Verbs for Expectation:
1. Present/Future Expectation:
āĻāĻĒāύি āϝāĻĻি āĻোāύāĻিāĻু āĻāĻāĻŦে āĻāĻļা āĻāϰেāύ āϝা āϏāĻŽ্āĻĒāϰ্āĻে āĻāĻĒāύি ā§§ā§Ļā§Ļ% āύিāĻļ্āĻিāϤ āύা, āĻāĻĒāύি should/shouldn’t āĻŦ্āϝāĻŦāĻšাāϰ āĻāϰāϤে āĻĒাāϰেāύ āϏেāĻ āĻāĻļা āĻĒ্āϰāĻাāĻļ āĻāϰāϤে।
If you expect something to happen of which you are not 100% sure, you may use should/shouldn’t to express the expectation.
Example:
- Your program is at 10:00 am. You should get ready now. (Present)
- Can you please help him to write the letter? It should take few minutes only. (Future)
- You have a cricket match You shouldn’t do party now. (Present)
- You are preparing yourself so well. You shouldn’t be a failure. (Future)
2. Past Expectation:
āĻāĻĒāύি āϝāĻĻি āĻāĻļা āĻāϰেāύ āϝে, āĻ āϤীāϤে āĻোāύāĻিāĻু āĻāĻāϤ, āϤāĻŦে āĻāĻĒāύি should have/ shouldn’t have+ verb-āĻāϰ past participle āĻŦ্āϝāĻŦāĻšাāϰ āĻāϰāĻŦেāύ।
If you expect something was supposed to happen in the past, you will use should have/ shouldn’t have+ verb’s past participle.
Example:
- I sent the parcel fifteen days ago. She should have received it by now.
- He is an experienced actor. He shouldn’t have made this mistake.
āϝেāĻšেāϤু, āĻāĻĒāύি āĻোāύ āĻĒāϰাāĻŽāϰ্āĻļ āĻŦা āĻŽāϤাāĻŽāϤ āĻĻিāϤে should/shouldn’t āĻŦ্āϝāĻŦāĻšাāϰ āĻāϰেāύ, āĻāĻĒāύি āĻ āϤীāϤেāϰ āĻāĻāύাāĻুāϞো āĻŦāϰ্āĻŖāύা āĻāϰāϤে āĻāĻŦং āϏেāĻুāϞো āĻাāϞ/āĻাāϰাāĻĒ/āĻ িāĻ/āĻুāϞ āĻšিāϏেāĻŦে āύিāϰ্āĻĻেāĻļ āĻāϰāϤেāĻ should have/ shouldn’t have āĻŦ্āϝāĻŦāĻšাāϰ āĻāϰāϤে āĻĒাāϰেāύ।
As you use should/shouldn’t for advising or suggesting something, you can also use should have/ shouldn’t have to explain things of the past and to denote them as good/bad/right/wrong.
Example:
- You should have done the course earlier because it really helped you to improve your skills.
- You should not have gone there because it was a wrong decision.
Modal Verbs for Probability:
1. Present/Future Probability
āĻāĻĒāύি may, might āĻāĻŦং could āĻŦ্āϝāĻŦāĻšাāϰ āĻāϰāϤে āĻĒাāϰেāύ āĻāĻŽāύāĻিāĻু āĻĒ্āϰāĻাāĻļ āĻāϰāϤে āϝা āĻŦāϰ্āϤāĻŽাāύে āĻŦা āĻāĻŦিāώ্āϝāϤে āĻāĻাāϰ āϏāĻŽ্āĻাāĻŦāύা āĻāĻে।
You can use may, might and could to express things that have a probability to happen in the present and future.
Example:
- She is in Dhanmondi now. She may come within 15 minutes. (Future)
- She is not at the office. She might be outside. (Present)
- Don’t eat that old food; it was kept outside the refrigerator. It could be poisonous. (Present)
- They might go on a world tour this month. (Future)
āϏāĻŽ্āĻাāĻŦāύা āĻŦোāĻাāϤে “might” āĻŦ্āϝāĻŦāĻšাāϰ āĻāϰাāĻ āĻļ্āϰেāώ্āĻ āĻাāϰāĻŖ “may”-āϰ āĻŦ্āϝāĻŦāĻšাāϰ āĻŦেāĻļ āĻāĻŽāĻ āĻĻেāĻা āϝাā§ āĻāĻŦং “could” āĻেāĻŦāϞāĻŽাāϤ্āϰ āĻšাঁāĻŦোāϧāĻ āĻ্āώেāϤ্āϰে āĻŦ্āϝāĻŦāĻšাāϰ āĻāϰা āϝাā§।
Using “might” is the best to denote probability because using “may” is less common and “could” can only be used in a positive sense.
Example:
- Many students are absent today. The Principal may not/ might not like this.
- He may not/might not be a popular actor, but his acting is really good.
2. Past Probability:
āĻāĻĒāύি āϝāĻĻি āĻ āϤীāϤেāϰ āĻোāύ āĻš্āϝাঁāϏূāĻāĻ āϏāĻŽ্āĻাāĻŦāύা āĻĒ্āϰāĻাāĻļ āĻāϰāϤে āĻাāύ, āϤāĻŦে may have/ might have/ could have + verb-āĻāϰ past participle form āĻŦ্āϝāĻŦāĻšাāϰ āĻāϰāϤে āĻĒাāϰেāύ। āĻāĻŦাāϰ, āĻāĻĒāύি āϝāĻĻি āĻ āϤীāϤেāϰ āĻোāύ āύাāĻŦোāϧāĻ āϏāĻŽ্āĻাāĻŦāύা āĻĒ্āϰāĻাāĻļ āĻāϰāϤে āĻাāύ, āϤāĻŦে may not have/might not have+ verb-āĻāϰ past participle form āĻŦ্āϝāĻŦāĻšাāϰ āĻāϰāϤে āĻĒাāϰেāύ।
If you want to express positive probability about past you can use, may have/ might have/ could have + verb’s past participle form. Again if you want to express negative probability about past you can use may not have/might not have+ verb’s past participle form.
Example:
- She is not in Dhaka. She might have gone to her hometown. (Positive)
- Hasan may have understood the work. Lisa was explaining it for a long time. (Positive)
- She is absent at the meeting. She may not have arrived yet. (Negative)
- He did not write the write the article. He might not have understood the topic well. (Negative)
āĻāĻĒāύাāĻে āĻŽāύে āϰাāĻāϤে āĻšāĻŦে āϝে, “could have” āĻেāĻŦāϞāĻŽাāϤ্āϰ āĻ āϤীāϤেāϰ āĻোāύ āĻ āϏāϤ্āϝ āĻ āĻŦāϏ্āĻĨা āĻŦোāĻাāϤে āĻŦ্āϝāĻŦāĻšৃāϤ āĻšā§, āϝা āĻāϏāϞে āĻāĻেāύি।
You should keep in mind that “could have” is only used to denote unreal conditions of the past which actually did not happen.
Example:
- Lira’s acting is really good. She could have won the contest if she had participated. (Positive)
āĻāĻĒāύাāĻে āĻāϰāĻ āĻŽāύে āϰাāĻāϤে āĻšāĻŦে āϝে, “couldn’t have” āĻেāĻŦāϞāĻŽাāϤ্āϰ āĻ āϤীāϤেāϰ āϝৌāĻ্āϤিāĻāĻাāĻŦে āĻ āϏāĻŽ্āĻāĻŦ āĻোāύāĻিāĻু āĻŦোāĻাāϤে āĻŦ্āϝāĻŦāĻšৃāϤ āĻšā§।
You should also keep in mind that “couldn’t have” is only used to denote logically impossible thing in the past.
Example:
- Aruba couldn’t have done the assignment. She was hospitalized then.







