如果说错误的话,你这里的or not 应该是对句子里的谓语否定的,就是说这样的话,你就成了whether he could or not arrive home on time,而我见你重点应该是on time,所以的话,就错了.就是你否定的重点不对.你应该这么说,he could arrive home whether on time or not?或者你直接说whether he could arrive home on time.