"The Atlantic is an ocean."
Translation:Cefnfor ydy môr Iwerydd.
Yet another wrong and already deleted sentence come back to haunt us. To be correct grammatically (even though completely nonsensical) it should read 'Cefnfor yw Môr Yr Iwerydd' = An ocean is the Atlantic Ocean ie 'The Atlantic Ocean is an ocean.
The Atlantic Ocean is Welsh is 'Môr Yr Iwerydd'