YOU SAID:
is that I have a bad idea
INTO JAPANESE
悪い考えがあります。
BACK INTO ENGLISH
Is a bad idea.
INTO JAPANESE
悪い考えです。
BACK INTO ENGLISH
It is a bad idea.
INTO JAPANESE
それは悪い考えです。
BACK INTO ENGLISH
It is a bad idea.
That didn't even make that much sense in English.