Given the potentially large challenges and costs such comprehensive peace-building often encompasses, it is essential to ensure that all key parts of the United Nations system are fully engaged in a collaborative and constructive fashion.
21. 因为这种综合性建立和平工作常常面临潜在的巨大挑战和费用，所以应确保联合国系统所有关键部门都充分参与配合，作出贡献。