YOU SAID:

They are a successful company

INTO JAPANESE

彼らは、成功した会社

BACK INTO ENGLISH

They're a successful company

INTO JAPANESE

彼らは成功した会社

BACK INTO ENGLISH

They would have a successful company

INTO JAPANESE

成功した会社があります。

BACK INTO ENGLISH

There are successful companies.

INTO JAPANESE

成功している企業があります。

BACK INTO ENGLISH

There are successful companies.