have got to do sth British I've got to return my library books today.
need to do Sth /,ni:d ts du: (sth)/ to have
to do something because you think it is necessary or someone else thinks it is necessary: We need to buy some more potatoes. I She told me I needed to get my hair cut. I Do I really need to go to this meeting?
be forced to do sth /bi: ,fb:rst ts du:
505
MUST
(sth)/ to have to do something that you do not want to do because you are in a situation that makes it impossible to avoid: She was forced to retire at the age of 50 because of health problems. I There was a train strike that day so we were forced to cancel the party.
feel obliged to do sth /fid z.bimdjd ta
du: (sth)/ to feel that you should do something because other people expect you to do it and will be disappointed or upset if you do not: / felt obliged to invite them all.
MUST
have no alternative h«v пэи
э:1'1з:гпэпу: to have to do something, even though you do not want to, because there is nothing else you can possibly do in the situation: The police say they hod no alternative: the man was armed and they had to shoot him. have no alternative but to do sth He had no alternative but to resign.
when you must not do something
see also forbid
must not/mustn't /'mAst not, 'тлч<ли use this to tell or order someone not to do something: This book must not be removed from the library. must not/mustn't do sth Remember, you mustn't tell Pat about this.
A
Only use must not/mustn't in the present tense. When talking about the past, use couldn't or wasn't/weren't allowed to: He couldn't stay in the US because he didn't have a green card. I The children were not allowed to watch horror movies. When talking about the future use will not be allowed to: Under the new rules, employees will not be allowed to smoke in the office.
A
Д Don't say 'you mustn't to go'. Say you mustn't go.
Don't confuse must not do something (-when you are not allowed to to it) and not have to do something (=when you can do it, but you do not need to).
Qcan't /karntflksent/ spoken use this to say that someone is not allowed to do something: "Ben wants to borrow the car." "Well tell him he can't." can't do sth Гт sorry, you know I can't discuss my work - it s secret.
A\ Only use can't in the present tense. When talking about the past, use couldn't or wasn't/weren't allowed to. When talking about the future, use will not be allowed to.
/К Don't say you can't to go'. Say you can't go.
not be allowed /not bi: a'laud/ if something is not allowed, there is a rule that forbids it: Smofcing is not allowed on the
train.
sb is not allowed to do sth You are not
allowed to use a dictionary during the test.
something that must be done
compulsory кэгг рлКч^п \adj] formal something that is compulsory must be done because of a rule or law: Compulsory education i=when all children have to go to school) was introduced in 1870.
it is compulsory for sb to do sth It's compulsory for all drivers to have insurance.
necessary /'nes^ri||-seri [ad/1 if something is necessary, there are very good reasons why it should be done, and it would not be sensible to avoid doing it: If any changes are necessary, you can make them.
it is necessary to do sth Is it really necessary to keep all the doors locked? it is necessary for sb to do sth The
doctor says it may be necessary for me
to have an operation.
make it necessary to do sth The heavy
rain made it necessary to close several
roads.
essential/vital /isenjX >aitl/ [adj] if
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something is essential or vital, it is very important to do it, and there could be serious problems if it is not done: Choosing the right equipment is vital. I In cases of heart attack, immediate medical help is absolutely essential. It is essential/vital to do sth It is vital to take precautions before handling toxic substances.
it is essential/vital that It is essential that you finish the job before Christmas. I It is vital that you keep accurate records of what you spend.
when you do not have to do something
not have to do sth not ha>v tn 'du:
A
(sth) if you do not have to do something, you can do it if you want, but you are not forced to do it. either by a rule or by another person, or by the situation you are in: Paola came from a wealthy family and didn't have to work. I You don't have to go if you don't want to.
Don't confuse not have to do something (=when you are not forced to do it) and must not do something
(=when you are not allowed to do it).
Qthere is no need to do sth floor
17 ni:d to du: (sth). spokon say this to
tell someone that it is not necessarv for
j
them to do something: There's no need to do the dishes - I'll do them in the morning. I There's no need to bring a towel - we have plenty.
unnecessary/not necessary лп
nesos<?ri. nnt 'nesos^ritj-scri [adj] if something is unnecessary or not necessary.
is it not needed or there is no good reason for you to do it: They want to build another shopping mall here, but we think it's completely unnecessary. + to do stH It 's not necessary to oil your bike every day.
not need to do sth (also needn't
Don't say 'you needn't to pay now'. Say you needn't pay now.
A
Don't confuse not need to do something (=when something is not necessary) and must not do something (=when something is not allowed).
do Sth British) not ni:d to du:(sth), ni:dnt du: (sth) to not have to do something because it is not necessary and there will not be any problems if you do not do it: You don't need to tell Sandy - she already knows, i You needn't come with me - I can find my own way to the station. I Mar/an had a rich husband and did not need to work.
A
optional 'оррпэЩ'спр-/ [adj] if something is optional, you do not have to do it or use it but you can if you want to: We all had to study English, but Spanish was optional.