Whether your cousin is tall or not.和 Is your cousin is tall

Whether your cousin is tall or not 这句子中的whether是个连词,经常与后面的or not连用,表示“不管是不是”的意思,不独立成句,而在复合句中充当一定的成分.比如：
Whether your cousin is tall or not is not my business.你表哥是高是矮跟我没关系.
I don't care whether your cousin is tall or not.我不在乎你表哥是高是矮.
Is your cousin is tall or short?这句话有毛病,把后面的is去掉,变成个疑问句,必须作出二选一的回答.