点WWithout引导的壮制作人：吴丽兰班级：高二（6）班:有时虚拟条件不用从句，而是通 过上下文或用介词短语等表示出 来，这种句子叫含蓄虚拟条件句。Without, but for, otherwise, or等词引导的含蓄虚拟条件句往 往可以改写成由if引导的虚拟条 件句。eg Without air, human being would not be able to survive (=lf there were no air):如果没有空气，人类将无法生存But for your timely help, we should not have completed this difficult task.(=lf it had nt bee n for your timely help.):要不是你及时帮助，我们就完成不 了这项艰巨的任务He was on business in Beijing at that time, otherwise he might have helped us. (=lf he had nt bee n on busi ness in Beijing at that time.):他那时候在北京出差，不然他可能 就帮我们了。eg： Luckily Mary telephone to inform me of the meeting, or I would have been absent. (=lf Mary had not telephone to inform me of the meeting.):幸好玛丽打电话通知我要开会，否 则我早就缺席会议了。