YOU SAID:

I am so cool it's unbelievable

INTO JAPANESE

私はそれは信じられないがカッコイイ

BACK INTO ENGLISH

I can't believe it is so cool

INTO JAPANESE

私はそれはとてもクールだなんて信じられない

BACK INTO ENGLISH

I can not believe it's so cool

INTO JAPANESE

私はそれがとてもクールだとは思わない

BACK INTO ENGLISH

I do not think it is very cool

INTO JAPANESE

私はそれが非常にクールだとは思わない

BACK INTO ENGLISH

I do not think it is very cool