Byddwn ni’n gallu dweud pethau fel ‘I would go’ yn Gymraeg gan ddefnyddio ‘Bod + yn + berfenw’ yn yr Amodol:
Bod + yn + berfenw (+ gweddill y frawddeg)
It is possible to express phrases such as the ones below, using the verb to be (in the conditional tense) + yn + verb:
Bod + yn + verb (+ the rest of the sentence)

I would go.                                Byddwn i’n mynd.
It would do you good.             Byddai fe’n gwneud lles i ti.
She would come.                     Byddai hi’n dod.
You would get a shock.          Byddet ti’n cael sioc. 

Yn ne Cymru, byddwn ni’n defnyddio ffurf cryno’r berfau afreolaidd (‘mynd, dod, cael, gwneud’) yn yr amodol fel rheol ar lafar bob dydd.
In south Wales it is more normal to use the short forms of the conditional tense with the irregular verbs  – mynd, dod, cael, gwneud – in everyday speech.

Byddwn ni’n ychwanegu terfyniadau’r amodol -wn i, -et ti, -ai fe/hi, -en ni, -ech chi, -en nhw at fôn y berfau:
The conditional endings  -wn i, -et ti, -ai fe/hi, -en ni, -ech chi, -en nhw  are added to the roots:

Mynd (El-),  Gwneud (Gw)nel-),  Cael (Cel- Gel– in speech),  Dod (Del-)

So instead of saying     –   Byddwn i’n mynd   I would go
The short way is used   –    Elwn i                     I would go

Instead of saying           –   Byddai fe’n gwneud lles i ti     It would do you good
The short way is used   –   ’Nelai fe les i ti                        It would do you good

Instead of saying            –   Byddai hi’n dod      She would come
The short way is used    –   Delai hi                    She would com

Instead of saying   –   Byddet ti’n cael sioc   You would have a shock
The short way is used     –    Gelet ti sioc      You would have a shock

Byddwn ni’n yngau ffurfiau’r amodol yma gyda ‘mynd, dod, cael, gwneud’ yr un fordd ag y byddwn ni’n ynganu pob ffurf arall ar yr amodol. Y sain ‘e‘ yw’r sain allweddol:
The same pronunciation rules apply as with all the conditional tenses.  The key sound is ‘e’:
-wn i                pronounced as            -en i
-ai fe/hi           pronounced as            -e fe/hi

Byddwn ni’n defnyddio ‘Ddim‘ i ffurfio’r negyddol, e.e:
‘Ddim
’ is added for negatives, e.g:
Elen ni ddim               –           We would not go

Byddwn ni’n gofyn cwestiynau ar lafar trwy ddefnyddio tôn llais, e.e:
Questions
– in speech – tone of voice, e.g:
Elet ti?                        –           Would you go?