YOU SAID:

I am not sure we can finish this task.

INTO JAPANESE

このタスクを終了することができることを確認ではないです。

BACK INTO ENGLISH

It is not sure that you can finish this task.

INTO JAPANESE

この作業を完了できるかどうかはわかりません。

BACK INTO ENGLISH

I do not know if I can complete this task or not.

INTO JAPANESE

- 僕に出来るかな？

BACK INTO ENGLISH

- I do not know if I can do this.

INTO JAPANESE

- 僕に出来るかな？

BACK INTO ENGLISH

- I do not know if I can do this.