However, because of the limit of resources and knowledge, there must be some insufficiency but will be improved by further study.

但由于笔者掌握的资料及知识视野的限制，文章中难免存在一些不足，还有待以后深入学习和研究。

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"For things to progress smoothly, there must be improved relations between the United States and North Korea, between North Korea and the European Union and between North Korea and Japan, " he told the New York Times.

CNN: North Korea reportedly backs U.S military presence

"There must be no inertia between now and early 2001: young people's life chances need to be improved as soon as possible, " said the minister.

BBC: London colleges lack 'strategy'