Adding H Before Vowels
H-prothesis means adding h to the front of a word that begins with a vowel: enw → ei henw hi (her name), arian → ein harian ni (our money).
How It Works
What adds h
- ei (her): ei henw hi her name
- ein (our): ein harian ni our money
- eu (their): eu hysgol nhw their school
- the short forms after a vowel: 'i (her), 'n (our), 'u and 'w (their): a'i hanes hi (and her story), gyda'n hathro ni (with our teacher), i'w hystafell (to her room, or to their room)
- 'm (my), mostly in writing: a'm hewythr (and my uncle); speech usually says a fy ewythr i
- the counting phrase ar hugain (literally on twenty): un ar hugain (21)
No h after ei (his), fy, dy or eich: ei enw e (his name), fy enw i, dy enw di, eich enw chi.
Why it matters. The h alone can tell you whose thing it is: ei henw (her name) but ei enw (his name).
In speech. After eu the h is nearly always heard. After ei (her) it is sometimes dropped in fast, casual speech, but it is always written.
Not every h. Words such as haul (sun) and hapus (happy) start with h anyway and keep it everywhere. H-prothesis is only the extra h on a vowel word. For the short forms, see Short Possessives After Vowels; for counting, see Traditional Counting in Twenties.
Examples (6)
- Mae ei henw hi ar y drws.
Her name is on the door.
enw → henw after ei (her).
- Mae ein harian ni yn y banc.
Our money is in the bank.
arian → harian after ein.
- Mae eu hysgol nhw'n fawr iawn.
Their school is very big.
ysgol → hysgol after eu.
- Aeth hi i'w hystafell.
She went to her room.
i + ei becomes i'w, which still adds h.
- Daeth Siân a'i hewythr i'r parti.
Siân and her uncle came to the party.
a + ei becomes a'i, which still adds h.
- Mae hi'n un ar hugain oed heddiw.
She's twenty-one today.
ugain → hugain in ar hugain.
Common Mistakes
Adding h after eich.
eich hysgol chieich ysgol chiEich never adds h. Only ei (her), ein and eu do.
Adding h after dy.
dy henw didy enw diDy causes soft mutation of consonants and does nothing to vowels.
How It Connects
Learn This First
H-prothesis generalises the h added after ei 'her', ein and eu.
Related Patterns
- Short Possessives 'm / 'i / 'n / 'wShort Possessives After Vowels
The short forms that also add h.
Level 4 - Traditional Numbers: un ar ddeg, ugainTraditional Counting in Twenties
Where ar hugain comes from.
Level 4 - Initial Consonant Mutations
How h-prothesis fits with the other changes.
Level 1 - ei 'his' + Soft MutationHis: Ei + Soft Mutation
Ei (his) never adds h.
Level 2
Words in This Pattern
Practice Adding H Before Vowels in Bubblegum
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