Modal auxiliaries in everyday English: How and When to Use in English
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Modal auxiliaries in everyday English
Modal auxiliary verbs allow us to express notions of ability, obligation, repetition, etc. They also allow us to conjugate other verbs in tenses other than the present.
Some commonly used auxiliary verbs:
• Can: ability to do something, possibility or permission:
Some commonly used auxiliary verbs:
• Can: ability to do something, possibility or permission:
Horatio can smell an animal in the jungle from miles away. Horatio is able to smell an animal in the jungle from miles away.
Susie can't come today. Susie is unable to come today.
Can I borrow this pen? Will you let me borrow this pen?
• Will: the future or wishes:
Bruno Delavigne will be here tomorrow. Bruno Delavigne is going to be here tomorrow.
I won't call him anymore. I don't plan to call him again in the future.
Will you stop making noise please? Please stop making noise!
• Must: obligation, duty or certainty:
You must fasten your seat belt. You are obliged to fasten your seat belt.
Must we report this conversation to Bruno? Do we have to report this conversation to Bruno?
Somebody is knocking on the door, it must be Bob. Somebody is knocking on the door, I'm sure it's Bob.
• May: uncertainty, probability, possibility:
We may arrive late tonight. Don't wait for us. It's possible that we will arrive late tonight. Don't wait for us.
May I talk to you for a minute sir? Could I talk to you for a minute sir? (formal)
Exercise 1
Hello friend. I buy you a drink sometime? I'd like to try to convert you to a different religion than your current one.
Hello friend. Can I buy you a drink sometime? I'd like to try to convert you to a different religion than your current one.
Can: 'Can' correctly poses the question in this construction. In this question, the speaker asks for permission, using the verb 'can', which agrees with the subject 'I'.
Does: 'Does' cannot be used with the subject 'I, which follows the auxiliary in this construction. We might ask however 'Do I look okay?' or 'Do I have something on my face?'. Or 'Does he know what he is doing?'
Need to: 'Need to' does not usually precede the subject of a sentence. Also, it does not make sense here. Occasionally 'Need I...?' is used to pose a question, but it expresses a question of necessity and not permission.
Am: 'Am' is a form of the verb 'to be'. It is never used to ask questions about capacity or permission. It can be used to pose other questions, for example: Am I speaking too loudly? or Am I bothering you? Using it in this construction is grammatically correct.
Exercise 2
Bob: Hi, Susie. I had a pretty crazy weekend. I lost three hundred dollars in a card game.
Susie: ? That very smart. I didn't know you gambled.
Bob: No, ! My wife says that I .
Susie: But you just told me that you lost your money playing cards.
Bob: Yeah. Someone stole my wallet while I was playing 'solitaire' on my phone.
Susie: ? That very smart. I didn't know you gambled.
Bob: No, ! My wife says that I .
Susie: But you just told me that you lost your money playing cards.
Bob: Yeah. Someone stole my wallet while I was playing 'solitaire' on my phone.
Bob: Hi, Susie. I had a pretty crazy weekend. I lost three hundred dollars in a card game.
Susie: You did 1? That wasn't 2 very smart. I didn't know you gambled.
Bob: No, I don't 3! My wife says that I can't 4.
Susie: But you just told me that you lost your money playing cards.
Bob: Yeah. Someone stole my wallet while I was playing 'solitaire' on my phone.
Susie: You did 1? That wasn't 2 very smart. I didn't know you gambled.
Bob: No, I don't 3! My wife says that I can't 4.
Susie: But you just told me that you lost your money playing cards.
Bob: Yeah. Someone stole my wallet while I was playing 'solitaire' on my phone.
1 You did: This is the best choice here. The auxiliary of surprise is always formed with the subject of the former statement and the auxiliary conjugated in the simple past tense (you did). Because no auxiliary is specified in the original statement, we know that we must use 'do'. Example: -I gave all my money to that homeless woman. -You did?
1 You lost: When responding to a statement with an expression of surprise, we use an auxiliary, and not a regular verb, such as 'lost'.
1 You have: 'You have' is incorrect because 'have' is not used as an auxiliary in the original statement (I lost three hundred dollars), and when an auxiliary is not specified, we usually use 'do'.
1 You are: 'You are' is incorrect because 'are' is not used as an auxiliary in the original statement (I lost three hundred dollars), and when an auxiliary is not specified, we usually use 'do'.
2 wasn't: This is the best choice here. The sentence requires a conjugated form of the verb 'to be', in the negative. To form the contraction of 'was not', we remove the letter 'o' from 'not' and replace it with an apostrophe. Example: Pressing that red button wasn't the smartest thing to do.
2 can't: 'That can't very smart' is grammatically incorrect.
2 weren't: Because Susie uses the singular pronoun 'that', we cannot use the plural contraction 'weren't' as an auxiliary. 'That weren't' is grammatically incorrect. Example: "Those weren't the same cats as before".
2 shouldn't: 'That shouldn't be very smart' is grammatically incorrect.
3 I don't: This is the best choice here. 'Yes or No' responses often follow the format of 'subject' + 'auxiliary' (I + do, in this case), and we always use whichever auxiliary has been used in the previous question. If an auxiliary has not been used, we typically use 'do'. Example: -I didn't know you had blonde hair. -I don't!
3 I go not: When responding to simple 'yes or no' questions, we use an auxiliary, rather than the main verb (go).
3 Don't I: 'Don't I' is the inverted form, and is usually used to ask a question, not to respond to one.
3 Go not I: 'Go not I' is grammatically incorrect.
4 can't: This is the best choice here. 'Can' is used to express capability or permission. Bob is saying that his wife does 'not allow him' to go to the casino. Example: My stepmother says I can't go to the ball tonight.
4 am not: 'I am not' does not make sense here.
4 go not: 'Go not' is grammatically incorrect. Negation is formed with an auxiliary when using verbs such as 'go'.
4 am not can: 'Am not can' is grammatically incorrect. We cannot use two auxiliaries ('am' and 'can') in a construction like this.
Exercise 3
Polly: What did you think about my report, Bruno?
Bruno: I noticed a few mistakes in it. You want to double check it.
Bruno: I noticed a few mistakes in it. You want to double check it.
Polly: What did you think about my report, Bruno?
Bruno: I noticed a few mistakes in it. You may want to double check it.
Bruno: I noticed a few mistakes in it. You may want to double check it.
may: 'May' is the correct answer. Bruno is politely suggesting that Polly double check the report. 'You may want to (do something)' is a common way of suggesting something without using the stronger imperative form.
could: We cannot use 'you could want' to make a suggestion. 'You could' generally means 'you would be capable of', for example: 'This job offers everything you could possibly want'.
must: The phrase 'you must want' expresses a strong sense of obligation, or an imperative statement. It is rare that we read or hear constructions with 'must want' together. If Bruno wanted to command or instruct Polly, he would simply say 'You must double check the report'.
Exercise 4
Mr. Delavigne called this morning to say that he be late for today's staff meeting. He asked if it would be to postpone the meeting, or at least save some cookies for him.
Mr. Delavigne called this morning to say that he might 1 be late for today's staff meeting. He asked if it would be possible 2 to postpone the meeting, or at least save some cookies for him.
1 might: 'Might' correctly expresses the possibility in this sentence.
1 possibly: We cannot use 'possibly' here because there is no auxiliary to precede it. However, we could say he 'will possibly be late' or 'he might possibly be late'.
2 possible: 'Possible' is the best choice here because the adjective 'possible' correctly expresses doubt or possibility. This sentence uses the expression 'to be possible'. Example: 'Will it be possible to travel by bus?'.
2 possibly: 'Possibly' is an adverb. We generally say 'to be possible', not 'to be possibly'.
Exercise 5
Luna: Hey Polly, do you know when Bruno's flight to arrive? I made him a special soup which will rejuvenate his depleted chakra energy.
Polly: I'm not exactly sure when his plane land. He to call me as soon as he arrives. Would you like me to give him a message for you?
Luna: Just tell him that someone cares about balancing his energy.
Polly: Will do.
Polly: I'm not exactly sure when his plane land. He to call me as soon as he arrives. Would you like me to give him a message for you?
Luna: Just tell him that someone cares about balancing his energy.
Polly: Will do.
Luna: Hey Polly, do you know when Bruno's flight is 1 to arrive? I made him a special soup which will rejuvenate his depleted chakra energy.
Polly: I'm not exactly sure when his plane will 2 land. He is 3 to call me as soon as he arrives. Would you like me to give him a message for you?
Luna: Just tell him that someone cares about balancing his energy.
Polly: Will do.
Polly: I'm not exactly sure when his plane will 2 land. He is 3 to call me as soon as he arrives. Would you like me to give him a message for you?
Luna: Just tell him that someone cares about balancing his energy.
Polly: Will do.
1 is: This is correct. The 'be + infinitive verb' construction expresses a future action which is likely to occur. In this case, Bruno's flight is 'due' or 'scheduled' to arrive tonight.
1 will: We cannot use the auxiliary 'will' here because of the infinitive form of the verb 'to arrive' follows it. This construction is grammatically incorrect. However, we could say 'When will Bruno's flight arrive?'
1 goes: We cannot use 'goes' here because the construction requires the verb 'to be' and not 'to go'. However we could say 'When is Bruno's flight 'going to arrive?'
2 will: This is the correct choice. We must use the auxiliary 'will' here because the verb 'land' is in the infinitive form (without the 'to').
2 is: We cannot use the 'be + infinitive verb' construction here because it requires that an infinitive verb, with 'to', follow it. For example, we could say 'Bruno's flight is to land tonight'.
3 is: This is the best choice here. The 'be + infinitive verb' construction expresses a future action which is expected to occur. In this case, Bruno is supposed to call Polly as soon as he lands.
3 supposed: We cannot use 'supposed' without a form of the verb 'to be' preceding it. We could say, however, Bruno is supposed to call me as soon as he arrives.
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