Meaning of -TH in English

-TH

suffix

BAD : It was their 23th wedding anniversary.

GOOD : It was their 23rd wedding anniversary.

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Use -th when the word for the number ends with '-th': '6th May' (= six th ), '18th May' (= eighteen th ). Do not use -th with (numbers ending) 1, 2, 3.

Compare: '1st May' (fir st ), '2nd May ' (seco nd ), '3rd May ' (thi rd )

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