Prohibition
e.g. He must not leavehis room for awhile. (Он не должен/ему
нельзя выходить из комнаты некоторое время.)
This meaning is expressed in negative sentences and must is
also followed by the simple infinitive.
Note, Absence of necessity (in Russian не нужно, нет необходимости) is ex-
pressed by other verbs (see to have and need).
Emphatic advice,
E.g.You must come andsee us when you're in London. You must stopworrying about your son. You mustn'tgive another thought to what he said. You mustn't miss the film. It is very good. You must have your hair cut. It's much too long. You mustn't cry.
This meaning is found in affirmative and negative sentences
and is closely connected with the two above mentioned meanings.
4) supposition implying strong probability,
e.g. He must beill. He looks so pale.
It must be late as the streets are deserted.
Must in this meaning is found only in affirmative sentences.
In Russian this meaning is generally rendered by means of the
attitudinal adverbs вероятно, должно быть.
In English this meaning may also be expressed by means of the
attitudinal adverb probably.
In this meaning must may be followed by different forms of
the infinitive. If reference is made to the present, the Continuous
infinitive is used with dynamic verbs.
e-g. The book is not on the shelf. Jane must be readingit.
Let's have something to eat. You must be starving.
Ifmust is followed by the simple infinitive of dynamic verbs,
it expresses obligation.
e-g. Jane must read the book.
You muststay here.
However, with stative verbs the simple infinitive is used to
express supposition.
e.g. He must beover fifty.
He must knowall about it as he has read a lot on the subject.
Must in combination with the Perfect infinitive refers the ac-
tion to the past.
e.g. Do you see him smoking over there? He must have finished
his work.
It is six o'clock. She must have comehome.
The combination of must with the Perfect Continuous infini-
tive indicates an action begun in the past and continued into the
moment of speaking.
e.g. It must have been rainingall the night. There are big pud-
dles in the garden.
However, if must is followed by a stative verb, the Perfect in-
finitive is used.
e.g. He must have beenhere since breakfast.
He must have knownit all along.
Note. Occasionally the combination of must with the Perfect Continuous infini-
tive may express an action going on at a given past moment.
e.g. He must have been writinga letter when I came.
When must expresses supposition implying strong probability,
its use is restricted in two ways:
a) It is not used with reference to the future. In this case we
find attitudinal adverbs in the sentence.
e.g. He will probably cometomorrow.
He will evidently knowall about it.
b) It is not used in the interrogative or negative form. It is
found only in the affirmative form.
Note. To express supposition implying strong probability with negative mean-
ing, in addition to attitudinal adverbs, the following means are employed:
e.g. He must have failedto get in touch with her.
He must have misunderstoodyou.
He must be unawareof that.
He must never have guessedthe truth.
No one must have toldhim about it.
§ 90. Note the following set phrases with must.
a) Must needsdenotes obligation.
e.g. He must needsgo there. (Он непременно должен пойти туда.)
b) / must be going and / must be off both mean 'it is time for
me to go* (in Russian Мне пора уходить).
c) / must tell you that... and / must say... are stereotyped
phrases in which the meaning of obligation is considerably weak-
ened inmust.
d) In the sentences: You must come and see me some time.
You must come and have dinner with me. You must come to our
party. You must come and stay with us for the week end and the
like, the meaning of obligation in must is also weakened. Must
has become part of such sentences which are a common way of ex-
pressing invitations.