Y bore oedd heulog yr haf, gwres yn llenwi'r awyr dros Gymru.

The summer morning was sunny, with heat filling the air over Wales.

Roedd Gareth yn sefyll tu allan i neuadd yr ysgol gymunedol yng Nghaerdydd.

Gareth stood outside the community school hall in Cardiff.

Roedd yn ddiwrnod pwysig – etholiad maer.

It was an important day – the mayoral election.

Roedd Gareth yn athro hanes, ond nid oedd bob amser yn glafoerio dros wleidyddiaeth.

Gareth was a history teacher, not always passionate about politics.

Ond heddiw, roedd yn wahanol.

But today was different.

Roedd rhaid iddo bleidleisio'n iawn i wneud argraff ar ei ffrind gwleidyddol, Rhys.

He had to vote correctly to impress his political friend, Rhys.

Wrth gerdded i mewn, cafodd croeso gan arolygydd pleidleisio gyfeillgar.

As he walked inside, he was greeted by a friendly polling inspector.

“Bore da, Gareth!” meddai’r dyn, gan wenu.

“Good morning, Gareth!” said the man, smiling.

Roedd Gareth yn hanner dychwelyd y cyfarch gyda gwên o ansicrwydd.

Gareth half-returned the greeting with a smile of uncertainty.

Roedd iard yr ysgol wedi'i thrawsffurfio'n ardal bleidleisio.

The schoolyard had been transformed into a polling area.

Roedd cyrtiau pêl-fasged wedi diflannu, yn eu lle cawsoch chi fwthiau pleidleisio a llwyth o daflenni gwybodaeth.

The basketball courts had disappeared, replaced by voting booths and loads of informational pamphlets.

Clywodd Gareth sŵn pêl-fasged yn rholio yn y cefndir, gan atgoffa pawb o swyddogaeth arferol y lle.

Gareth heard the sound of a basketball rolling in the background, reminding everyone of the place's usual function.

Roedd dau fwth ar wahân – un gyda llun enfys "Ymarfer Eich Pleidlais" a'r llall yn nodi "Go Iawn."

There were two separate booths – one with a rainbow image labeled "Practice Your Vote" and the other labeled "Real Vote."

Wrth weld pobl yn pleidleisio, penderfynodd Gareth fynd at y bost "Ymarfer Eich Pleidlais."

Seeing people voting, Gareth decided to go to the "Practice Your Vote" booth.

Gafodd ei ganllawiau gan ddyn ifanc gyda thaflenni.

He received instructions from a young man with pamphlets.

Rhoddodd Gareth ei bapur yn y blwch gan wenu balch.

Gareth placed his paper in the box, smiling proudly.

Ond wedyn sinfau!

But then, embarrassment struck!

Sylweddolodd nad oedd hynny'n gywir.

He realized that wasn't correct.

Cyfartal a go stwnsio ei gerdyn gan leyrodd Gareth.

He twisted his card and cried out.

Dagrau poeni roedd yn cronni yn ei llygaid.

Tears of worry started to gather in his eyes.

“Peidiwch â phoeni, dewch yma,” meddai’r swyddog pleidleisio cyfeillgar, yn awgrymu Gareth i fynd i bwth y go iawn.

“Don't worry, come here,” said the friendly polling officer, suggesting Gareth go to the real vote booth.

Dechreuodd Gareth bwyntio a phowtio, “Dw i wedi pleidleisio'n barod...yn y bwth anghywir...”

Gareth started pointing and pouting, “I've already voted... in the wrong booth...”

Chwarddodd yr swyddog.

The officer laughed.

“Pleidlais ymarfer oedd honno, Gareth.

“That was a practice vote, Gareth.

Dim ond chwara teg yw!

It's just fair play!

Dewch, pleidleisiwch yma.”

Come, vote here.”

Da!

Good!

Aeth Gareth i’r go-iawn bwth a phleidleisiodd.

Gareth went to the real booth and cast his vote.

Teimlodd y don o ryddhad.

He felt a wave of relief.

Wrth adael, gwnaeth cysylltu â’r swyddog pleidleisio, diolch eto.

As he left, he made contact with the polling officer, thanking him again.

Roedd yn falch bod wedi gofyn am help - teimlad braf.

He was glad he had asked for help – it felt good.

A phan roedd Gareth yn cerdded allan i'r haul hafol, roedd yn teimlo newid.

And as Gareth walked out into the summer sun, he felt a change.

Roedd yn teimlo'n fwy hyderus a llonydd.

He felt more confident and calm.

Roedd wedi gwneud peth cywir, ac roedd yn gwybod ei fod wedi rhoi enghraifft dda i'w ffrind Rhys a phawb.

He had done the right thing and knew he had set a good example for his friend Rhys and everyone else.