I have no idea _when___he will come back.(whether可以吗?如果可以那if

I have no idea _when___he will come back.(whether可以吗?如果可以那if I have no idea （that） when he will come back home那个位置可以有that i have no idea that he will come back. i have no idea that when he will come back .错在哪? I have no idea( )he will win.是填whether还是that?如果改成I have some i have no idea __ she will be back tomorrow. I have no idea____he will come back from work. 489．I have no idea________ he will come back. It does not matter whether he will come?这句话中的whether可以用if代替吗 I have no idea _____ he will come there.When he comes,I will I have just come back.是现在完成时吗?如果是,那come为什么不用过去分词? I have no idea,后面可以直接接从句?