根据首字母及汉语提示，完成下列单词的拼写，使句意明确，语言通顺。
(1)What do you like to do in your f____ (空闲的) time?
(2)I could hear her sweet v____  (噪音) from the next room.
(3)Travelling by plane is expensive, but it s____ (节省) time.
(4)Would you please make a shopping l____  (清单) for the picnic?
(5)It's polite to k____  (敲) on the door before entering a room.