YOU SAID:

What happened to it is the best and worst thing ever.

INTO JAPANESE

最高と最悪の事に何が起こったかです。

BACK INTO ENGLISH

And what has happened to the worst thing is.

INTO JAPANESE

最悪の事態に何が起こったのです。

BACK INTO ENGLISH

It is the worst thing happened.

INTO JAPANESE

それは最悪の事態が起こった。

BACK INTO ENGLISH

It is the worst has happened.

INTO JAPANESE

最悪の事態が起こったのです。

BACK INTO ENGLISH

It is the worst thing that happened.

INTO JAPANESE

それは、起こった最悪のことです。

BACK INTO ENGLISH

It is the worst thing that happened.