Understanding the Differences Between 'Two-thirds of the Cake' and 'Two-thirds of a Cake'

When discussing fractions and their grammatical usage, it's essential to understand the nuances that can arise in English sentences. This article explores the subtle differences between saying 'two-thirds of the cake' and 'two-thirds of a cake', and how verb agreement plays a crucial role in these contexts. We'll also discuss the concord rule and examples to clarify these grammatical subtleties.

The Subtlety in Differences

According to some, there's a slight difference between the two phrases, 'I ate two-thirds of cake' and 'I ate two-thirds of a cake'. In the first phrase, the speaker is indicating that they ate some cake but is not specifying which cake it was. In the second phrase, the speaker is referring to a particular cake that was on the table or somewhere else. Although these phrases are often interchangeable, it's more precise to use the second phrase when referring to a particular item.

The Concord Rule

One important rule to remember in English is the concord rule, which states that a verb should agree with the preceding noun or clause when the subject is a fraction, percentage, or an indefinite pronoun. This rule guides us in determining whether to use a singular or plural verb form.

Singular Verbs

Singular verbs are used in the following examples:

40 percent is enough to qualify in this examination. Three-fourths of the portion has been completed. A half of the stock is exhausted.

Plural Verbs

Plural verbs are used in the following examples:

A half of the class have agreed to come for the evening session. One-fourth of the total strength are absent today. Many have lost their property in a flood.

Your Example: 'Two-thirds'

When we say 'two-thirds of the cake', it is generally considered singular. Therefore, the correct form would be:

Two-thirds of the cake was consumed.

However, if the cake is divided into distinct parts and some of these parts are eaten, the verb should be plural:

Two-thirds of the cake were consumed.

Colloquial Usage and Clarifications

According to Mick McDermott, the usage of singular or plural verbs also depends on whether we are using a number as a measurement of one item or counting distinct elements. For instance:

Two-thirds of the cake is a single amount, so the verb is singular: 'Two-thirds of the cake was consumed.' Two-thirds of the cake is being represented as distinct parts eaten, so the verb is plural: 'Two-thirds of the cake were consumed.'

Similarly, another example to illustrate this:

'2/3rds of the applicants were men' '2/3rds of a tank of petrol was used on the trip'

Conclusion

While there are some subtle but important differences in the way we use these phrases, understanding the concord rule and applying it correctly can help enhance the clarity and precision of your writing. Whether you choose to use 'two-thirds of the cake' or 'two-thirds of a cake', being mindful of verb agreement is key to maintaining grammatical accuracy.