単なる推測だろ。の英語

You're just guessing.

It was just an assumption.

That is a guess to the end.

It's no more than a guess.

It's guesswork [conjecture] (and nothing more).

Those are thoroughly rumors.

It's only make-believe.

That is only an illusion.

a mere assumption

That is only a guide.

I think it is a mere coincidence.

It's merely a joke.

That is just a plan.

It is a mere conjecture.

That is only a guide.

It's an illusion.

That is a reference to the end.

Your guess is wide of the mark.

It's (a) mere theory.

That's incidental to my story.

It is a mere misspelling.

I only meant it as a joke.

That's just a lie.

This is a simple confirmation.

It is nothing but a joke.

I only meant it as a joke.

I am a mere assistant.

It is a mere conjecture.

I only meant it as a joke.

It is an alarming. rumour.