Even though 11th, 12th, and 13th end in 1, 2, and 3, they still take “th” because of their special spelling and pronunciation: 11th, 12th, 13th (not 11st, 12nd, or 13rd)

The correct form is 11th, not 11st. This rule applies because ordinal numbers in English always end with the last two letters of the word written out fully. For example, “first” ends in “st,” “second” ends in “nd,” “third” ends in “rd,” and “ fourth ” ends in “th.”

When it comes to the ordinal number for “11,” there is often confusion between “11th” and “11st.” In this article, we will explore which form is correct and why. To put it bluntly, the correct ordinal number for “11” is “11th.” The use of “11st” is incorrect and considered grammatically wrong.

Correct spelling, explanation: this ordinal number should be written as 11th because they don’t pronounce it with first at the end (which would then indicate -st suffix), but we pronounce it eleventh, so with -th at the end.

Look up eleventh in Wiktionary, the free dictionary. Eleventh or 11th may refer to:

Common exceptions (all the 'teens') always use "th": 11th, 12th, 13th. Always write or speak the ordinal spelling as "first", "second", "third", etc., and use symbols for informal lists or tables (“21st birthday”, “5th place”).

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