Modal verbs
E.g. Can she have been waiting for us so long?
Could with reference to the present is also used in this way, implying more uncertainty.
E.g. Could it be true?
Could she be telling lies?
Could he have said if?
Could she have been waiting for us so long?
In Russian both variants, with can and could, are rendered in the same way: Неужели это правда? Неужели он лжет? And so on.
Improbability
E.g. It can’t be true. (Это не может быть правдой. Вряд ли это так.)
In this meaning can is found only in negative sentences, which are often emotionally colored. Depending on the time reference, this can is also used with different forms of the infinitive/
E.g. He can’t be really ill.
She can’t be telling lies.
He can’t have said it.
She can’t have been at home all this time.
She can’t have been waiting for us so long.
Could is also used in this way making the statement less categorical
E.g. It couldn’t be true.
She couldn’t be telling lies.
He couldn’t have said it.
She couldn’t have been at home all this time.
She couldn’t have been waiting for us so long.
Can and could followed by different forms of the infinitive, are found in special questions where they are used for emotional coloring (to express puzzlement, impatience, etc.).
E.g. What can (could) he mean?
What can (could) he be doing?
What can (could) he have done?
Where can (could) he have gone to?
It can be rendered in Russian as: Что, собственно, он имеет в виду?
As is seen from the above examples, the form could referring to present is sometimes clearly opposed to can in that it expresses unreality whereas can expresses reality. This may be observed in the following meanings:
ability – He can speak English. He could speak English if necessary.
possibility due to circumstances – You can get the book from the library. You could get the book from the library if necessary. E.g. “You can have a million books on our television screen, and even more. There is nothing to throw away.” (I. Asimov)
“How could a man be a teacher? “ (I. Asimov)
In the other meanings, however, this difference between the two forms is obliterated. Could is used either as a milder or mote polite form of can as a form implying more uncertainty than can:
permission – Can I use your pen? Could I use your pen? (more polite)
uncertainty, doubt, improbability – Can it be true? Could it be true (less certain). It can’t be true. It couldn’t be true (less certain).
We can also find some examples of modal verbs usage in some newspapers , magazines or in literature.
E.g. It could be true but it is advisable to find out first what has really happened there. (Может быть, это и правда, но лучше сначала выяснить, что же действительно там произошло.)
“Honey, you couldn’t support a wife,” she answered cheerfully. “Anyway, I know you too well to fall in love with you.” (F. Scott Fitzgerald)
In this case the verb could is used here in the meaning of doubt, uncertainty and improbability.
May
The modal verb may has the following forms: may – the Present tense (e.g. it may be true) and might – the Past tense. The form might is used in two ways: a) in past-time contexts, mainly in reported speech in accordance with the rules of the sequence of tenses (e.g. He told me that it might be true) and b) in present-time contexts as a milder and more polite form of may, or as a form implying more uncertainty than may (e.g. Might I come and see you? It might be true), or to express unreality (e.g. He might have fallen ill if he hadn’t taken the pills).
May has the following meanings:
1) supposition implying uncertainty
E.g. He may be busy getting ready for his trip.
In Russian this meaning is generally rendered by means of the modal adverbs возможно and может быть.
In English this meaning may also be rendered by means of the attitudinal adverbs perhaps and maybe.
In the meaning of supposition implying uncertainty the verb may occurs in affirmative and negative sentences.
E.g. He may be at home.
He may not be at home (Возможно, что его нет дома).
Two factors may temporarily have increased their caution. (W. Faulkner)
In this meaning may can be followed by different forms of the infinitive depending on the time reference expressed.
May in combination with the simple infinitive usually refers the action to the future.
E.g. He may come soon.
The action may also refer to the present but only with stative verbs.
E.g. He may be ill.
He may not know about it.
May in combination with the Continuous infinitive of dynamic verbs refers the action to the present.
E.g. It’s too late to phone him now. He may be sleeping.
I never see him about now. For all I know, he may be writing a book.
May in combination with the Perfect infinitive refers the action to the past.
E.g. He may have fallen ill.
“What’s happened to the dog?” I asked. “It isn’t here. His master may have taken it with him.”
The combination of may with the Perfect infinitive may also indicate an action begun in the past and continued into the moment of speaking. This is usually found with stative verbs.
E.g. He may have been at home from about two hours.
However, if may is followed by a dynamic verb, the Perfect Continuous infinitive is used.
E.g. He may have been waiting for us for an hour.
In the meaning of supposition implying uncertainty, the form might is also found. It differs from the form may in that it emphasizes the idea of uncertainty. It may be followed by the simple, Continuous or Perfect infinitive.
E.g. He might come soon. He might be ill.
He might be doing his lesson now. He might have spoken to her yesterday.
possibility due to circumstances
E.g. You may order a taxi by telephone.
A useful rough-and-ready rule is that rime adverbs may come at either end of the sentence, but not in the middle.
May in this meaning occurs only in affirmative sentences and is followed only by the simple infinitive.
The form might is used in past-time contexts in accordance with the rules of the sequence of the tenses.
E.g. He said the might order a taxi by telephone.
Might followed by the Perfect Infinitive indicates that the action was not carried out owning to certain circumstances (expressed in the sentence or implied).
E.g. He might have fallen ill if he hadn’t taken the medicine.
Luckily he wasn’t driving the car. He might have been hurt.
You are so careless. You might have broken the cup. (Ты чуть было не разбил чашку).
It seemed to him that the most interesting thing in life was what might lie just around the corner. (O. Henry)
permission
E.g. The director is alone now. So you may see him now.
If you have got a car and can drive, you may spend part of your holiday moving from place to place. (C. Eckersley)
May in this meaning is found in affirmative sentences, in interrogative sentences which usually express a request, and in negative sentences where it denotes prohibition. But in negative sentences it is not common as prohibition is generally expressed by other modal verbs (see can and must).
E.g. You may smoke in here. May I smoke in here? You may not smoke in here.
In this meaning may is combined only with the simple infinitive. In interrogative sentences the form might is also found when we wish to express a more polite request.
E.g. May I join you?
In reported speech the form might is used.
E.g. He told me that I might smoke in the room He asked me if he might join us.
disapproval or reproach
E.g. You might carry the parcel for me. You might have helped me.
Here we find only the form might used in affirmative sentences and followed by the simple of Perfect infinitive. In the latter case it expressed reproach for the nonperformance of an action.
The form might which expresses unreality is not always parallel to may. Might expresses unreality only in combination with the Perfect infinitive.
E.g. You might have let me know about it beforehand.
There was a car accident in front of our house. Luckily Tommy was at school. He might have been killed.
In most cases might is used as a milder and more polite form than may of as a form implying a greater degree of uncertainty:
permission – May I call to my mother now? Might I call to my mother now? (very polite)
Might I take the liberty of pointing out that you have made a small mistake? (J. Joyce)
supposition – He may come a little later. He might come a little later (less certain).
The Chancellor’s measures might help towards an agreement on an incomes policy. (Moscow News).
The two forms are not opposed in the meaning of possibility due to circumstances where only may is used, nor in the meaning of disapproval of reproach where might alone is found.
E.g. You may find the book at the library.
You might have considered your parents’ feelings.
May as well (might as well, might just as well) + infinitive is a very mild and an emphatic way of expressing an intention. It is also used to suggest of recommend an action.
E.g. I may as well take the child with me. (Я, пожалуй, возьму ребенка с собой. Пожалуй, будет лучше, если я возьму ребенка с собой).
You may as well give him the letter. I might as well stay at home tonight.
“I’ll go at six.” “That’s far too late; you might just as well not go at all.” (Можно было бы и не ходить туда совсем).
It might have been worse means “Things are not so bad after all.” In Russian it is rendered as: Могло бы быть и хуже or в конце концов дела обстоят не так уж и плохо).
He might have been a … means ‘He might have been taken for a …’ ‘He looked as a …’
E.g. Roy Wilson, the new doctor, was twenty-eight, large, heavy, mature and blond. He might have been a