not interchangeable or able to substitute one for another;
"a rare incommutable skill"
例句
With the prevalence of PC &maturation of communication facility, Internet has entered into lots of families and become one of incommutable parts in our life. 随着电脑的普及以及通信设备的成熟。互联网已经走入了千家万户。成为我们生活中不可取代的一部分。
A rare,incommutable skill. 宝贵的、千金不换的技艺
The time-varying and incommutable character of the coefficient matrix of periodically time-varying linear systems are the bottleneck of the design for high precision direct integration methods. 周期时变线性系统系数矩阵的时变性与不可交换性是其精细积分算法设计中的瓶颈。
