Translation:The turtle walks and the dog runs.
Technically, tartaruga is turtle, and cágado is tortoise.
But it's very common to use "tartaruga" instead of "cágado". So, in common language, tartaruga could be both turtle and tortoise.
Muito obrigado por a sua ajuda! (Though, having looked at the dictionary and knowing how often I get accents wrong, I think I'll stick to tartaruga!)