按要求改写句子。
(1)The children are playing football.(用what就划线部分提问)
(2)Many people like the spring. (改为否定句)
(3)Did you buy presents on your holiday ?(否定回答)
(4)I am going to Shanghai at 3 o'clock.(用when 就划线部分提问)
(5)I went to school on foot (改为一般疑问句)