Should you write ‘31th’ or ‘31st'? Ordinal numbers can be difficult to remember how to use if English isn’t your first language because they change with different numbers. But we’ll cover ordinal numbers, plus how to use this one correctly in a sentence.
The short answer is:
Writing ordinal numbers can be tricky for someone learning English for the first time. But with a bit of practice, you’ll be well-versed in how to write ordinal numbers, no matter how high you’re trying to count.
An ordinal number is “a number designating the place (such as first, second, or third) occupied by an item in an ordered sequence” and “a number assigned to an ordered set that designates both order of its elements and its cardinal number,” according to Merriam Webster.
Here’s how ordinal numbers would be written in word form:
In numerical form, they’d be written like this:
The key is to remember that ordinal numbers generally repeat after 10 (with a few exceptions). For example, 11 would be eleventh (not like first).
But after this, we go back to using “first” just like we did with number one in the beginning of our count.
It would look like this:
This follows the first set of cardinal numbers we started with (first, second, third, etc.). From there, you’d simply follow this all the way up to 100. It’s odd that the numbers 11 through 20 follow a different set of rules than the rest of the numbers, but that’s just how it is.
As you learned above, it’s only correct to say ‘31st’ and not ‘31th.’
The difference between the two is that the former is ungrammatical and incorrect, and the latter is the correct way to write the ordinal version of the number.
Now that you’ve learned how to write ordinal numbers and you know what order they follow, you can write your own ordinal numbers. Use the following examples as a guide.
Here’s how you’d use ‘31st’ in a sentence correctly:
Now that you know the correct way to use ordinal numbers, you can use them correctly in your writing and in everyday life.
If you ever get stuck, just pop back on over and browse our library of articles on confusing words.
We can also teach you how to write better and understand common English idioms.
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