pivot burnisher

例句：

1. 1. Thepivot of the machine is located atthe bottom.
   机器的支点位于底部。
2. 2.The pivot of the policy was toreduce taxes.
   政策的核心是减税。
3. 3. Thepivot of the discussion was on the futureof the company.
   讨论的核心是公司的未来。