Cy: Ym mis Awst, wrth i'r haul ysblennydd ddisgleirio dros Draeth Heulog, roedd Cariad a Tesni yn barod i ddechrau eu trip ysgol.
En: In August, as the splendid sun shone over Sunny Beach, Cariad and Tesni were ready to start their school trip.

Cy: Roedd y diwrnod yn braf a'r traeth yn edrych fel rhan o baradwys - tywod euraidd, dŵr clir, a chlogwyni gwyrddlas o gwmpas.
En: The day was fine, and the beach looked like part of paradise - golden sand, clear water, and green cliffs around.

Cy: Roedd mor braf yma fel y byddai unrhyw un yn teimlo eu bod ar wyliau.
En: It was so pleasant here that anyone would feel like they were on holiday.

Cy: Ond nid gwyliau oedd hyn, roedd yn drip ysgol.
En: But this was not a holiday; it was a school trip.

Cy: Cariad, gyda'i gwallt melyn a llygaid glas, oedd y ferch mwyaf chwilfrydig yn y dosbarth.
En: Cariad, with her blonde hair and blue eyes, was the most curious girl in the class.

Cy: Roed hi wastad yn darllen llyfrau am fioleg y môr, ac am bysgod, crancod, a phopeth arall yn y dŵr.
En: She was always reading books about marine biology, and about fish, crabs, and everything else in the water.

Cy: Tesni, ei ffrind gorau, roedd yn fwy ofalus.
En: Tesni, her best friend, was more cautious.

Cy: Roedd hi'n ddigon hapus i ddarllen amddiffyniadau ar gyfer ecwibwynt a pharodrwydd.
En: She was quite happy to read about defenses for ecosystems and preparedness.

Cy: Wrth gerdded ar hyd y traeth, Cariad yn sydyn yn troi at Tesni, “Tesni, wyt ti wedi clywed am y llecyn cawraidd o dan y dŵr ger yma? Mae pawb yn sôn amdano.”
En: While walking along the beach, Cariad suddenly turned to Tesni, "Tesni, have you heard about the giant spot underwater near here? Everyone is talking about it."

Cy: “Ydyn,” meddai Tesni yn ofalus. “Ond mae'n beryglus iawn ac mae’r athrawon wedi dweud 'na i fynd yno.”
En: "Yes," said Tesni cautiously. "But it's very dangerous and the teachers said not to go there."

Cy: Cariad, yn llawn antur ac awydd, meddai, “Rydyn ni'n gallu edrych, dim ond am funud. Beth ddylet ti ddweud?”
En: Cariad, full of adventure and eagerness, said, "We can just look, just for a minute. What do you think?"

Cy: Tesni wnaeth dweud ynddo hi, “Cariad, mae'n beryglus iawn... Ond dw i’n dod gyda ti. Dim ond i wneud yn siŵr dy fod di'n saff.”
En: Tesni sighed, “Cariad, it’s very dangerous... But I’ll go with you. Just to make sure you’re safe.”

Cy: Pan aeth yr athrawon i'r sied pysgod ar gyfer y sesiwn nesaf, Cariad a Tesni gwnaeth casglu eu hofferyn nofio a llithro oddi ar y traeth yn dawel.
En: When the teachers went to the fish shed for the next session, Cariad and Tesni gathered their swimming gear and quietly slipped away from the beach.

Cy: Daethon nhw’n gyflym at gwch bach, wedi ei angori’n gynnil ar ymylon y dŵr.
En: They quickly came upon a small boat, discreetly anchored at the water’s edge.

Cy: Gydag ychydig o alebion cyflym ac atgar, nofiodd y ddau ferch at y cwch a gwibio tuag at y rhewlif tanddwr mêl.
En: With a few quick and encouraging glances, the two girls swam to the boat and sped towards the hidden underwater glacier.

Cy: Roedden nhw'n teimlo’r cyffro o droi cornel y traeth a gweld ceg y lecyn o'u blaenau.
En: They felt the thrill of turning the corner of the beach and seeing the mouth of the spot ahead of them.

Cy: Cariad a Tesni daeth o hyd i’r llecyn, a heb betruso, plymion nhw i’r dŵr oer a chlir.
En: Cariad and Tesni found the spot, and without hesitation, they dived into the cold, clear water.

Cy: Wrth iddo fynd yn dywyllach, aethon nhw’n bellach i'r llecyn lle roedd lleoedd o dywod euraidd ac algau uchelgeisiol.
En: As it got darker, they went deeper into the spot where there were patches of golden sand and ambitious algae.

Cy: Allai Cariad ddim helpu ond wenu wrth i Tesni edrych yn nerfus o'i chwmpas. “Edrych! Mor hyfryd!” gwaeddodd Cariad.
En: Cariad couldn’t help but smile as Tesni looked nervously around her. "Look! How lovely!" shouted Cariad.

Cy: Ond yn sydyn, clywsant som brawychus - y llanw oedd yn byrhau’r agorfa!
En: But suddenly, they heard a terrifying sound - the tide was closing the opening!

Cy: Tesni roedden yn teimlo ei chalon ronci. “Mae’n rhaid i ni fynd, nawr!” meddai hi’n daer.
En: Tesni felt her heart race. “We have to go, now!” she said urgently.

Cy: Cariad arweiniodd eu ffordd yn ôl gyda phenderfyniad.
En: Cariad led the way back with determination.

Cy: Wrth iddyn nhw nofio, lle'r oedd cynt ar agor, nawr roedd llif y dŵr yn ôlaf i fewn.
En: As they swam, where once it was open, now the water flow was narrowing in.

Cy: Wrth i'r dŵr cnuddi'w mynwes, roedd yn amlwg y rhifinnau'n cyfyngu.
En: As the water pulled at them, it was clear the opening was closing.

Cy: Roedd y gwarchodfa'n pwyntio cefn yn dynn erbyn pêl morol.
En: The sanctuary turned into a tight race against the marine current.

Cy: Gyda chyffwrdd ac undod, roedd Cariad a Tesni yn llwyddo’n ddiweddar dod o hyd i'r agorfa yn ail ac yn taflu’i hunain ato.
En: With touch and unity, Cariad and Tesni finally managed to find the opening again and hurled themselves towards it.

Cy: Roedden nhw'n rhydd!
En: They were free!

Cy: Wrth iddyn nhw bron cyrraedd ar y lan, fe welsant y naill at ei gilydd, gorau ydyn nhw, a gwenu.
En: As they nearly reached the shore, they looked at each other, best friends, and smiled.

Cy: Cariad, wedi dysgu gwers werthfawr am barodrwydd a perygl, aeth yn gyflym i ymddiheuro pan cyrhaeddodd yr athrawon yn bryderus.
En: Cariad, having learned a valuable lesson about readiness and danger, quickly went to apologize when the concerned teachers arrived.

Cy: “Pwy a feddyliodd,” meddai Tesni wedyn, “byddwn ni’n dysgu mwy am fywyd y môr... a’m bywyd ein hunain heddiw.”
En: “Who would have thought,” said Tesni afterward, “we would learn more about marine life... and our own life today.”

Cy: Cariad, yn gwenu’n braf, cyffyrddodd llaw Tesni’n barchus diolch.
En: Cariad, smiling brightly, touched Tesni’s hand respectfully in thanks.

Cy: Gyda'r haul yn aros gwenu arnynt, dylen nhw bellach dysgu gwersi ychwanegol, dilyn rheolau ond hefyd archwilio gyda chynllun a pharaniad.
En: With the sun continuing to smile upon them, they now had extra lessons to learn, follow the rules but also explore with a plan and preparation.

Cy: Roedd diwrnod ola'r trip ysgol wedi troi yn brofiad i'w gofio bob haf!
En: The last day of the school trip had turned into an experience to remember every summer!