Visual Guide: How to Write and Spell Numbers 21 Through 30 in English Correctly
By Elena Rostova
Q1: Is "twenty one" written with or without a hyphen in standard English?
A1: It must always be written with a hyphen: "twenty-one." Every compound number between 21 and 99 requires a hyphen when written in words.
Q2: How do you write 30th in words?
A2: The written ordinal form of 30 is "thirtieth." The final -y from "thirty" changes to -ie before adding the standard -th suffix.
Q3: Why do native speakers pronounce thirty as "thur-dee"?
A3: This occurs primarily in North American English due to a linguistic process called intervocalic flapping. When a /t/ sound appears between vowels after a stressed syllable, it turns into a brief alveolar flap that sounds identical to a soft /d/.
Q4: Do numbers like 20 and 30 end with the same sound as numbers ending in -teen?
A4: No. Decades like twenty and thirty end with an open /i/ vowel sound and drop the nasal consonant entirely. Numbers like thirteen and fourteen end with a closed /n/ consonant sound and take strong syllable stress.
Elena Rostova holds a Master's degree in Public Health Journalism. She covers groundbreaking medical research, holistic wellness trends, mental health awareness, and nutritional science.
