何とも言えないな。の英語

I can't say for sure.

I cannot say.

I can't say.

I just don't know what to say.

That's hard to say.

I am not certain [sure].

I can't say for certain.

I don't know what to say.

I'm at a loss for words.

I can't say anything.

There is no way of expressing it―It is unspeakable―unutterable.

（文頭に置けば）―There is no saying―（文尾に置けば）―for aught one knows―（独立句に用いれば）―Who knows?―God knows―（形容詞に用いれば）―unspeakable sorrow―inexpressible feeling―indescribable beauty―unutterable grief―ineffable joy―indefinable charm―exquisite pleasure

Who knows?

God knows.

Don't say anything.

Say nothing.

Can't say anything

It's not worth mentioning.

What can I say about it?

I have nothing to say about it.

No comment!

You know what it is.

It goes without saying.

I told you so!

There is no saying what may happen.

I have nothing to say.

I'm not going to tell you.

Of course, it is exceedingly unlikely.

I do not know what excuse to make.

I'm not saying anything.