1·At Japanese electronics maker Omron, sales representatives identify product development opportunities by finding customers' unsolved problems; they ask broad questions and observe what doesn't work.
日本的电子设备制造商欧姆龙，销售代表通过从客户使用的角度来发现未解决的问题以寻求改善产品的机遇；他们拜访顾客，征询方方面面的问题，并密切观察产品让客户不满意的地方。
2·The origin of electrification in clouds is an old and still unsolved problem .
云中起电的缘由是一个古老但仍未解决的问题。
3·Symbolic dynamical system is a powerful tool in the study of dynamical systems theories, the study of dynamical properties of the general symbolic dynamical system is a far unsolved problem.
符号动力系统是动力系统理论研究的强有力工具，一般符号动力系统的动力学性质的研究是一个远未解决的课题。
4·However, there are still a number of unsolved problems in this field.
然而，在这个领域中还存在许多未解决的问题。
5·Analytic number theory is fortunate to have one of the most famous unsolved problems, the Riemann hypothesis.
解析数论非常幸运还有一个最为有名的未解决的问题，即黎曼假设。