Meaning of ONE in English
BAD : Fluency in English is one of the best qualifications you can have.
GOOD : Fluency in English is one of the best qualifications you can have.
Do not use the in front of one of : 'We stayed at one of the cheaper hotels.' 'She is one of the strongest political leaders in the world today.'
BAD : The sea is one of our main source of food.
GOOD : The sea is one of our main sources of food.
The noun/pronoun following one of is always plural: 'one of my friends', 'one of her teachers', 'one of the biggest islands in the world'.
BAD : One of the eggs were bad.
GOOD : One of the eggs was bad.
DUBIOUS : She is one of those children who refuses to share things.
GOOD : She is one of those children who refuse to share things.
After a phrase beginning with one of , the verb is singular: 'One of the main disadvantages is the cost of the battery.'
However when one of is followed by a relative clause, the verb in the relative clause can be singular or plural, depending on the meaning: 'I had a long talk to one of his daughters, who is married to an architect.' 'We were introduced to one of the consultants, who were gathered together in the foyer.' In cases where a singular verb and a plural verb seem equally possible, careful users generally prefer a plural verb: 'Peter is one of those people who are always prepared to help.'
BAD : After we had been to Helen's house, we went to Paul's one.
GOOD : After we had been to Helen's house, we went to Paul's.
Avoid one/ones immediately after an -'s/-s' form, especially in formal styles: 'No, it's not mine - it's my wife's.' Compare: 'John's new one is the same as yours.' (= -'s/-s' form + adjective + noun)
BAD : If you can carry those books, I'll bring these ones.
GOOD : If you can carry those books, I'll bring these.
BAD : This book will be of interest to all those ones involved in the tourist industry.
GOOD : This book will be of interest to all those involved in the tourist industry.
Avoid ones immediately after these/those , especially in formal styles: 'Within this group, there are those who are willing to take risks and those who are more cautious.'
Compare: 'These plastic ones are cheaper.' (= these/those + adjective + noun)
BAD : All the shoes and handbags they sell are handmade ones.
GOOD : All the shoes and handbags they sell are handmade.
Avoid one/ones after an adjective which can be used on its own, especially in formal styles: 'The new proposals are impractical.'
Compare: 'We could do with a new one/some new ones.'
BAD : British children have more opportunities than Tunisian ones.
GOOD : British children have more opportunities than Tunisian children.
BAD : Young people learn more quickly than older ones.
GOOD : Young people learn more quickly than older people.
Ones is usually used to refer to things: 'Rechargeable batteries are more expensive than ordinary ones.' 'The red ones are fine, but I prefer the white ones.' Ones may also be used to refer to particular people: 'The older children laughed but the younger ones were scared.'
In general statements about groups of people, ones is usually avoided: 'French students have to work harder than British students.'
BAD : One mustn't waste ones time when there is so much to do.
GOOD : One mustn't waste one's time when there is so much to do.
BAD : Getting married for economic reasons is not a good start to ones married life.
GOOD : Getting married for economic reasons is not a good start to one's married life.
See also IT (↑ it )'S
BAD : One cannot succeed unless he works hard.
GOOD : One cannot succeed unless one works hard.
In British English (unlike American English) it is not possible to change from one to he/his/her/ etc .
Note, however, that most speakers find the repetition of one awkward and try to avoid it: 'One cannot succeed without working hard.' 'Success calls for a lot of hard work.'
Avoiding sexism in your writing
In the past, when people referred to a member of a group containing both men and women (or boys and girls), they used the pronouns he/him/his :
A good doctor listens carefully to his patients.
Anyone who wants to join should give his name to the secretary.
Nowadays, many people feel that this usage is unfair to women. If you want to avoid the danger of seeming sexist, you can use one of the following alternatives.
Use They/Them/Their to refer back to an indefinite pronoun (anyone, somebody etc) :
Anyone who wants to join should give their name to the secretary.
Some people object to this usage in formal styles, insisting that they (plural) does not agree in number with anyone (singular). This usage is nevertheless very common.
Make all the forms plural:
Good doctors listen carefully to their patients.
Those who want to join should give their name to the secretary.
Design the sentence in such a way that a personal pronoun is not needed. For example, instead of saying ‘If anyone wants to go now, he may do so’, just say ‘Anyone who wants to go now may do so.’
Use he or she, his or her, etc :
A good doctor listens carefully to his or her patients.
This alternative is found in formal writing, and so is the use of he/she, his/her, s/he, etc.
However, they are generally felt to produce awkward and unnatural sentences, especially when they are repeated, as in:
If a doctor listens to his or her patients, he or she will be in a better position to help them.
See EVERYONE 1 (↑ everyone )
Longman Common Errors English vocabulary. Английский словарь распространенных ошибок Longman. 2012