"A crab is not a dog."
Translation:게는 개가 아닙니다.
The pronunciation is still rather different. When they read dog (개), the mouth opens bigger horizontally with a little emphasize. While for crab (게), they read it with less intense feeling.
There used to be a slight difference in sound no longer than few decades ago. But it's gone among most of the people. Sooo you can only guess
Is word order important here? I switched the subject and topic, and I was marked wrong.
I'm still confused word order and the 는 versus 가 ending. What roles do they play here to distinguish "a dog is not a crab" from "a crab is not a dog"?
In this sentence, '는' is a postposition which can replace '이/가', the subjective postposition. So '게는' is the subject. But '가' here is a complement postposition, so '개가' is the complement. So, "A dog is not a crab" would be "개는 게가 아닙니다" and "A crab is not a dog" would be "게는 개가 아닙니다".