My father taught me to do additions and subtractions .

我爸爸教我做加减法。

The addition of those three , without any real subtractions , should translate into a playoff run in portland this coming season .

三位猛将的加入，同时没有任何的减弱，将足以保证下个赛季波特兰的季后赛之路。

" In the course of implementation of the contract , all the alterations , amendments , supplements and subtractions to the contract have been agreed upon and signed in written documents through consultation by both parties . "

本合同执行中，对其条款的任何变更、修改和增减，都须经双方协商同意并签署书面文件