I'm not sure where you did see that sentence, but could find the one at fairy tale books or generally books for children. You could also find it at another books. For instance, from a book "Three little pigs", if the wolf says in Korean, "다 잡아 먹어 버릴꺼야.", which mens the wolf will eat all three pigs up.. He's greedy. He's going to eat everything. Speaking of the each meaning of words, "다" --> all, everything. "잡아" --> It's a verb "잡다". It literally means "catch" or "take" but in this sentence, it's combined with a verb "먹다(eat)", so the wolf catch three pigs and then eat them. But interestingly, verb "잡아 먹다" is generally used for animals...well, if you're a farmer, raise some livestocks such as chicken or something, you could use a verb "잡아 먹다". Or, if you're going to snatch something at a farm, you'd also use it. In conclusion, "잡아 먹다" is more highliting than "먹다". But it has a nuance, which is a kind of quite wild something.. ^^