3. 다음 두 문장을 한 문장으로 고쳐 쓸 때, 빈칸 (A), (B)에 들어갈 말로 가장 적절한 것은?
(1) I have a friend. He speaks four languages. -> I have a friend (A)__________ speaks four languages.
(2) I know the city. It has a beautiful river. -> I know the city (B)__________ has a beautiful river.