YOU SAID:

I don't think this will work, although it might, and yet I do not know and cannot be sure.

INTO JAPANESE

私はこれがうまくいくとは思わないが、それでも私は知らないし、確信が持てない。

BACK INTO ENGLISH

I don't think this will work, but still I don't know and I'm not sure.

INTO JAPANESE

私はこれがうまくいくとは思わないが、それでも私は知らないし、私は確信していない。

BACK INTO ENGLISH

I don't think this will work, but still I don't know and I'm not sure.