I have a dream is over the rainbow.

I have a dream is over the rainbow.
I have a dream is over the rainbow.

I have a dream is over the rainbow.
这个句子有语法问题,有 have 和 is 两个谓语动词.我想你要表达的意思是：
我有个梦想,它就是穿越（飞越）彩虹.