How are ‘one’ and ‘ones’ used as a replacement?

The English words one and ones are, among other things, pronouns and, in this role, replace previously mentioned information in conversations – something that is usually represented by a noun in the sentence. In this way, it can be communicated effectively as known things do not have to be repeated unnecessarily. There is only one difference between the two: ‘one’ is required for singular and ‘ones’ for plural reference.

Attention: In this function, they are not to be confused with the numeral ‘one’ or the adverb ‘once’. Further possible meanings are briefly explained below.

Moreover, some issues may occur when translating from or into other languages in which it is possible to use adjectives without a comparable prop-word. A direct translation from such a language into English may result in a sentence like:

• “Are you going to bake the cake with sweet or sour apples? – With sweet, of course.”

Compare the following explanations for a specific usage:

What can ‘one’ replace?

The word ‘one’ designates the quantity ‘one’ and thus replaces nouns that are used in the singular form. These can be things, animals, and also people:

• “The next train leaves in an hour. The last one has just left.”
  • In this example, the noun ‘train’ is replaced by ‘one’. The adjective ‘last’ cannot stand alone, and the repetition of the term ‘train’ would sound odd. ‘One’ can, therefore, not be omitted:
  • So, it is not possible to say: “The last has just left.”
• “Could you give me my jacket, please? – Of course, is it the brown one?”
  • In this case, ‘one’ replaces ‘jacket’. Just as in the example above, it would not be correct to state this English sentence without the prop-word:
  • Not possible: “Of course, is it the brown?”

What can ‘ones’ replace?

The same applies to ‘ones’. The only thing is that the substituted noun is in the plural:

• “These shoes are better. The ones I tried before didn’t fit well.”
  • In this sentence, ‘ones’ stands for several ‘shoes’, and so the plural form ‘ones’ needs to be used too.
  • Wrong would be: “The I tried before …”

Attention: In general, it is essential that the named item or person is known; otherwise, the statement becomes unclear. It would, therefore, be incomprehensible to say:

• “He’s bought the one.”

Where and with what words can ‘one/ones’ appear in a sentence?

There are several other parts of speech with which ‘one’ and ‘ones’ can occur in a sentence. Irrespective of this, however, they always refer to nouns. In detail, they appear in the following positions:

• After the definite article ‘the’:
  • “Is this the restaurant you went to last Saturday?”
  • “Is this the one you went to last Saturday?”
• After adjectives (such as ‘small, fast, hard, blue’), which can also be compared:
  • “I like the red shoes more.”
  • “I like the red ones more.”
    • Here, ‘ones’ stands for the plural noun ‘shoes’ and cannot be omitted.
    • Incomplete would be: “I like the red more.”
  • “The best player wins a prize.”
  • “The best one wins a prize.”
    • In this example, we have the adjective ‘good’ in its compared form ‘best’, which comes before ‘one’. It would not be possible without ‘one’ either:
    • Not: “The best wins a prize.”
• After the demonstrative pronouns ‘this, these, that’, and ‘those’:
  • “That cookie looks delicious.”
  • “That one looks delicious.”
  • “That looks delicious.”
    • Without ‘one’, this statement would also be possible.
• After the question word ‘which’:
  • “There’s ice cream and pudding. Which one would you like?”
  • “Which one is bigger? Russia or Canada?”

Which functions can ‘one’ have additionally?

In addition to the use as mentioned above, there are further functions that ‘one’ can adopt. However, different rules need to be followed:

• The word ‘one’ can also be an indefinite pronoun. Then, it is used as the impersonal ‘you’:
  • “One should always consider the environment.”
  • “It always depends on one’s ability to understand complex structures.”
    • As in this example, it can also express possession (the genitive) in this function – which is rarely the case.
• Furthermore, it is known as the number ‘one’, of course. Emphasising or amplification is not so well-known but undoubtedly common with the term ‘one’:
  • “Don’t forget to buy potatoes. There’s just one left.”
    • Here, it expresses the quantity ‘one’.
  • “Let’s just meet one day next month.”
    • This comment is about a point in time in the future that has not been precisely determined yet.
  • “I can tell you; Frank is one good friend.”
    • Here, it serves as amplification as a synonym for ‘a great friend’.

Note: And now a hint to avoid confusion. The pronoun ‘one’ (and especially ‘ones’) is not related to the adverb ‘once’ at all, which means ‘one time’:

• “I’ve been to Greece only once.”
• “We play squash there once a week.”
  • ‘one time’ could be used instead of ‘once’ in both sentences without changing their meanings.

Further explanations related to the ‘Prop-words ‘one’ and ‘ones’’

The following explanations are related to the topic ‘‘one & ones’ as a replacement for nouns’ and may also be helpful:

• Use of pronouns in English grammar
• Parts of speech in English grammar
• Exercise 1: use of ‘one’ and ‘ones’