YOU SAID:

I have no idea what to say.

INTO JAPANESE

私は何を言うには考えています。

BACK INTO ENGLISH

I believe in what you say.

INTO JAPANESE

あなたの言うことと思います。

BACK INTO ENGLISH

I think what you say.

INTO JAPANESE

私はあなたが言うと思います。

BACK INTO ENGLISH

I think I tell you.

INTO JAPANESE

私はあなたを教えてくださいと思います。

BACK INTO ENGLISH

I think I should tell you.

INTO JAPANESE

教えてくださいと思います。

BACK INTO ENGLISH

Please let me know.

INTO JAPANESE

私に知らせてください。

BACK INTO ENGLISH

Please let me know.