There are seven days in a/the week

Question

What is correct and why? Both, or only one of the following sentences?

1 - There are seven days in a week.

-> One single week consists of seven days. 1 week = a week = 7 days.

2 - There are seven days in the week.

-> "The week" as a general notion. The only Week class for for all the single instances. Having 7 days is a class property, not an instance property.

Similarly:

A cat has four legs or The cat has four legs?

A star consists of hot gases or The star consists of hot gases?

In the last two examples I can imagine also a plural, so Cats have four legs or The cats have four legs?

As for the week, the sentence "Weeks have seven days" sounds strange. Why?

Note that you can use the to indicate a generality, but context is important. — Andrew Leach, Jul 07 '14 at 15:42
possible duplicate of Are there any simple rules for choosing the definite vs. indefinite (vs. none) article? — phenry, Jul 07 '14 at 16:17
PLEASE, all the English native speakers, try to understand that the articles are a very difficult topic for a non-native speaker. Do not mark the question as duplicate just with reference to some more generic answer! For native speakers of languages which do not have / do not need articles it's not so easy as you may feel. — Honza Zidek, Jul 07 '14 at 17:15
If anglophones had to justify all the usages of the articles, we'd all speak French. — Edwin Ashworth, Jul 07 '14 at 23:41
@EdwinAshworth - you have no clue what pain it is to learn articles for users of languages which do not have such redundant, superfluous, illogical, obstructive things as articles :) Try to imagine you have to artificially add into your sentences some extra words every now and then which you mentally do not need, which you do not have in your head when thinking about the ideas you wish to express. And then you ask the native speakers for help and they flag your question as "to be closed", just with a reference to some general answer. This is even more annoying than the articles themselves :( — Honza Zidek, Jul 08 '14 at 16:46

score 5 · Accepted Answer · edited Jun 15 '20 at 07:40

5

Generally, your analysis is correct. Normally the refers to an identified individual or individuals, but it also has a (rather literary) use with generalisations - what you have called class properties.

However, there are more subtleties.

A cat has four legs and

The cat has four legs

both work for the general reading.

But

The star consists of hot gases.

does not work. This has only a specific reading (a particular star) and not a general reading, at least for me. I think this is because general the requires a super-class within which to distinguish the items. So (general) the cat is distinguished from dogs, horses, etc. But there is no obvious super-class within which stars are just one kind. (This may not be the reason, but it's the best thought I have had).

For the same reason

There are seven days in the week.

doesn't work for me with a general reading, though my judgment is less clear than for stars.

In your last examples,

Cats have four legs.

is fine, but

The cats have four legs.

can only be read as specific cats, not general. General the must be singular. Weeks have seven days is unusual, but perfectly grammatical.

edited Jun 15 '20 at 07:40

Community

1

answered Jul 07 '14 at 18:20

Colin Fine

77,173

1

+1, but the difference I see between days in a* week* and days in the* week* is that the former would normally be a simple accounting (the period of time we call a week is seven times the length of the period we call a day), while the latter would normally be used leading up to an enumeration of the days (and they are called Monday, Tuesday,...). Or, to put it slightly differently, the a version refers to a generic week (which could be any of many) while the the version refers to the Platonic essence of The Week (of which there is but one). – bye Jul 07 '14 at 19:28
@bye - The Platonic essence of The Week - that's exactly my understanding of the class notion in object-oriented programming. – Honza Zidek Jul 08 '14 at 15:29
1

John Lawler (who often comments here) wrote an answer which addresses several of your questions, though it doesn't address my question of why the star consists of hot gases doesn't work. – Colin Fine Jul 08 '14 at 16:21
@ColinFine After long time, I read again the John Lawler's answer http://www-personal.umich.edu/~jlawler/000001.html you recommended 8 years ago, and still I don't understand why "There are seven days in the week" should be wrong. It sounds exactly to me like John's example "The madrigal is polyphonic" (being polyphonic is characteristic of madrigrals) - having 7 days is indeed characteristic of weeks in the same way as having their days named Monday, Tuesday, ... :) And the natural super-class is unit of time :) Or would it sound better in "The Jewish week has 7 days"? – Honza Zidek Dec 16 '22 at 08:53

score 1 · Answer 2 · edited Jul 07 '14 at 18:08

I can see where the use of "a" and "the" might confuse you if English is your second language. In the sentences you posed as examples, "the" is used when describing a specific week, while "a" is used when the week could be any week. Therefore both sentences are correct but have slightly different meanings. The cat, star, and cats sentences are all correct for the same reason. As for the sentence "Weeks have seven days" sounding strange to you I have no idea, but it is grammatically correct.

I do not have a degree in English, but I was blessed with a grandmother who taught college level English, and lovingly corrected my grammar in my childhood.

score 1 · Answer 3 · answered Jul 08 '14 at 03:23

In addition to what others have said --

There are seven days in a week.
The seven days of the week are Monday, Tuesday,...

In (1), the statement is about an arbitrary week: For all x such that x is a week, x has seven days.

In (2), the statement is about the general concept week: It is defined as a sequence of these seven days: Monday, Tuesday,....

There are seven days in a/the week

3 Answers3