1·It is a problem difficult to solve.
这是一个难解决的问题。
2·I meet a problem difficult to solve.
我遇到一个难以解决的问题。
3·It is a problem difficult to work out.
这是一个难以解决的问题。
4·It is a problem difficult to work out.
这是一道难以解决的问题。
5·Power network planning is a NP hard problem difficult to be solved.
电网规划是一个较难解决的NP难问题。
6·Completion stealing is a problem difficult to deal with in protocol communication between CPU and PCI bus.
事务窃取一直是困扰CPU与PCI总线实现协议通信的难题。
7·We will show that the traditional mixed integer programming approach makes the problem difficult to represent and solve.
我们将说明传统的混合整数规划方法使问题难以描述和解决。
8·Incrustation of evaporator liquid room was the general existence and a problem difficult to solve in black liquid evaporation.
造纸黑液治理技术中，蒸发器结垢是黑液蒸发中普遍存在而难以解决的问题之一。
9·Rapid removing of compressed snow on urban roads has been a problem difficult to solve. There is no efficient and practical machine for it presently.
城市道路压实积雪的快速清除一直是较难解决的问题。目前，仍没有高效实用的除雪机械。
10·Synergistic effects, nonlinear variation, and difficulties in discounting the future make the intellectual problem difficult, but not (in principle) insoluble.
这项智力难题因协同作用，非线性变化，和考虑将来而变得困难，但(原则上)不是不可能解决。