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31st or 31th – Which is Correct?

When it comes to discussing dates, the confusion between using “31st” or “31th” is a common issue that many English learners face. So, which one is correct? The answer is straightforward – “31st” is the correct spelling to use when referring to the last day of the month. In this article, I will explain why “31st” is the correct choice, provide some examples to illustrate its usage, and share a simple analogy to help you remember this rule.

Let’s start with the explanation. In written English, when we want to indicate the ordinal number for the last day of the month, we add “st” to the number. For example, “31” becomes “31st” when we want to say “thirty-first.” This convention is consistent across the English language and is widely accepted and understood by native speakers.

To further illustrate this point, let’s consider some examples. Suppose you want to write the date as “October 31st.” By using “31st,” you are correctly indicating that it is the 31st day of the month of October. Here, “31st” serves as an ordinal number, representing the numerical position of that specific day within the month.

Now, imagine if we were to use “31th” instead. This would not only be incorrect but also confusing for native English speakers. Why? Because the suffix “-th” is used for every other date in the month. For example, “18th” for the 18th day or “25th” for the 25th day. If we were to write “31th” as the ordinal form of “31,” it would break the consistent and logical pattern that we find for every other date in the month.

To help you remember this rule, I like to use a simple analogy. Consider a line of people waiting to enter a club. Each person is assigned a number, representing their position in line. Now, if you were the 31st person in line, you would be referred to as “the 31st” and not “the 31th.” The same logic applies to dates. Just like you wouldn’t use “31th” to describe your position in line, you don’t use it to describe the last day of the month.

In conclusion, when it comes to indicating the last day of the month, the correct spelling is “31st.” This is because the suffix “-st” is used to form ordinal numbers, including “thirty-first.” It is important to use the correct spelling to ensure clarity and understanding when communicating in English. So, the next time you write a date, remember to choose “31st” to accurately represent the last day of the month.