it doesn't matter后面加that还是if?

it doesn't matter后面加that还是if?
it doesn't matter后面加that还是if?

it doesn't matter后面加that还是if?
都可以.
例句：It doesn't matter that you can't come.你不能来也没关系
It doesn't matter if/whether you will come.你能不能来都没关系

后面不加东西啊？！

that

that