whether or not例如:It ceased to matter whether or not he sold his work. 他是否卖掉了他的作品已无关紧要。if例如：I wonder if she is ill.不知她是否病了。whether例如：His nationality isn't relevant to whether he's a good teacher. 他的国籍与他是否是位好老师无关。I'm uncertain whether to go or not.我不能肯定去还是不去。
