YOU SAID:

My sister Sarah is a terrible singer, but she thinks she is a good singer.

INTO JAPANESE

私の妹のサラはひどい歌手が、彼女は彼女は良い歌手だと考えています。

BACK INTO ENGLISH

I think my sister Sarah terrible singer she is good singer she.

INTO JAPANESE

彼女は踊るのが上手だと私は思います。

BACK INTO ENGLISH

I think she is good at dancing.

INTO JAPANESE

彼女は踊るのが上手だと私は思います。

BACK INTO ENGLISH

I think she is good at dancing.