"줬어요" Actually means just verb. Like I gave (Past verb) If you just say "카메라를 빌려줬어요" -> It involves just subject implied, verb, and object. People can be confused because you didn't mention an indirect object ( like to whom? to what?). Even the first sentence (제가 카메라를 빌려줄 테니까 다음 주에 돌려주세요) doesn't have any indirect object.('you' is just implied in sentence.) The Reason I know that there is direction implied in first sentence is that subject mentions both borrowing and returning to one indirect object(implied 'you'). I'll borrow camera (to you) and give it back to me please. But even in Korean we don't imply direction often. That's just exceptional case i think. If you have any more questions, comment on it!