例句與造句

1. In view of the refinery practice , mathematical programming technique is used to construct the scheduling model , heuristic rules are applied to reduce the constraints and variables number in order to simplify the problem
   根據煉油行業的實際情況，用數學規劃方法建立各個功能模塊的調度模型，運用啟發式規則降低約束和變量的個數，從而降低問題的復雜性，是本文采用的一個主要方法。
2. It's difficult to find constraint and variables in a sentence. 用constraint and variables造句挺難的