it takes me about 20minuters to walk to school = I spend about 20minuters walking to school . 花费时间做某事的用法. it takes time to do sth sb waste time dong sth. to walk to school 中前面的是it takes time to do sth搭配的用法,后面的to 的是介词. 如果改为回家则是:it takes me about 20minuters to go home.就没有第二个to,home是地点副词 其前面不能加介词to .