Soft Mutation
Soft mutation is the most common Welsh mutation. It "softens" nine first letters, as in cath → gath and mam → fam.
How It Works
The nine changes:
- p → b: pen (head) → ben
- t → d: tad (father) → dad
- c → g: cath (cat) → gath
- b → f: bara (bread) → fara
- d → dd: desg (desk) → ddesg
- g → (disappears): gardd (garden) → ardd
- m → f: mam (mum) → fam
- ll → l: llyfr (book) → lyfr
- rh → r: rhaglen (programme) → raglen
Notice that b and m both become f, so a word starting with f might come from either.
Common causes you will meet first:
- i (to) and o (from): i Gaerdydd, o Fangor. See Going To and Coming From.
- the article before a feminine singular noun: y gath. See Soft Mutation After Y With Feminine Nouns.
- yn before a describing word: Mae hi'n dda. See Describing With Yn.
- dyma, dyna and dacw: Dyma fara. See Dyma, Dyna, Dacw.
- an adjective after a feminine noun: cath fach. See feminine noun + soft-mutated adjective.
- the thing owned in Mae gen i gar. See mae gen i.
Many prepositions cause it too; see prepositions with soft mutation.
Two limits. After the article and after the describing yn, words starting with ll and rh stay as they are: y llwy, Mae'n llawn. And the yn before a verb-noun causes no change at all: Dw i'n canu. See Bod + Yn + Verb-Noun.
Examples (6)
- Dw i'n dod o Bontypridd.
I come from Pontypridd.
p → b after o (from).
- Dyma dad Siân.
This is Siân's dad.
t → d after dyma.
- Wyt ti'n mynd i Fangor?
Are you going to Bangor?
b → f after i (to).
- Dyma raglen dda.
Here's a good programme.
rh → r after dyma; da softens to dda after the feminine noun rhaglen.
- Mae'r ardd yn fawr.
The garden is big.
g disappears after the article because gardd is feminine, so y becomes yr; mawr softens to fawr after yn.
- Dw i'n mynd i Lanelli yfory.
I'm going to Llanelli tomorrow.
ll → l after i (to).
Common Mistakes
Keeping y after a soft mutation has removed a g.
Dw i'n eistedd yn y ardd.Dw i'n eistedd yn yr ardd.When soft mutation drops the g of gardd, the word starts with a vowel, so the article must be yr.
How It Connects
Learn This First
Soft mutation is the first and most common mutation system; its source lists the nine changes with their own examples.
Related Patterns
- y + Feminine NounSoft Mutation After Y with Feminine Nouns
One of the first places soft mutation appears.
Level 1 - Predicative yn + Soft MutationDescribing with Yn + Soft Mutation
Describing words soften after yn.
Level 1 - dyma / dyna / dacwHere Is, There Is: Dyma, Dyna, Dacw
Pointing words that cause soft mutation.
Level 1 - mynd i / dod oGoing to and Coming from
I and o soften place names.
Level 1 - am, ar, at, dan, dros, drwy, gan, heb, i, o, wrth + Soft MutationSoft Mutation After Prepositions
The full list of softening prepositions.
Level 2
Learn Next
Patterns that build on this one.
- dydd Llun / nos LunDays of the WeekLevel 1
- Mae gen i (North)Having in the North: Mae Gen ILevel 1
- dy + Soft MutationYour (Ti): Dy + Soft MutationLevel 2
- ei 'his' + Soft MutationHis: Ei + Soft MutationLevel 2
- Fyddi di? / Fydda i ddimFuture Questions and Negatives of BodLevel 2
- mae 'naThere Is in Speech: Mae 'NaLevel 2
- neu + Soft MutationOr: Neu + Soft MutationLevel 2
- pa + Soft MutationWhich: Pa + Soft MutationLevel 2
And 5 more in the full list.
Practice Soft Mutation in Bubblegum
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