5. The dispute shall be submitted for arbitration by a mutually nominated arbitrator.
争议应由双方提名的仲裁者来仲裁。
还能这样说：
The mutually nominated arbitrator should submit the dispute for arbitration.
The mutually nominated arbitrator should arbitrate the dispute.
应用解析：
nominate sb. as... 任命某人为……
nominate sb. for... 提名某人为……的候选人；
nominate sb. to 任命某人为……的成员

6. We may discuss to agree upon a temporary arbitral body when needed.
我们讨论同意需要时成立一个临时的仲裁委员会。
还能这样说：
We will make a discussion about a temporary arbitral body when it is needed.
We will discuss to found a temporary arbitral body when needed.
应用解析：
body clock 生物钟；
body language 身体语言

7. Since this dispute is not negotiable, it is necessary to resort to arbitration.
既然争议不能协商解决，有必要将其诉诸仲裁。
还能这样说：
It is necessary to resort to arbitration if this dispute cannot be settled by negotiation.
The dispute which cannot be negotiated will resort to arbitration.
谚语：
Don't wait for a rainy day to fix the roof.
未雨绸缪。

8. We are now applying formally to the arbitration commission for arbitration of this dispute.
我们现在正式向仲裁委员会就此争议仲裁。
还能这样说：
We are applying for a formal arbitration to the arbitration commission.
We are about to apply to the arbitration commission to arbitrate the dispute.
应用解析：
acceptance commission 承兑手续费；
agricultural commission 农业委员会；
arbitration commission 仲裁委员会