.관계대명사) 뒷문장이 불완전해야 한다.what vs that ?? 둘다 뒤에게 불완전한데 어떻게 구분하나요?두 문장의 차이점은 ?ex) I saw the picture that ... , ism[입자]dust, dirt, sand, salt, pepper, suger, rice, flour, wheat, corn, grass, hair[스포츠와 다른 활동 ... ]baseball, soccer, tennis, motocross, chess, swimming, fishing, skydiving, shopping, traveling, working, s