The children ceremony completes with the "Oath of Allegiance" is purely symbolic.

本次典礼以孩子们一同向美国宣誓效忠结束，尽管整个过程完全都是象征性的。

The contents of its research primarily includes the completes with the stability of district land ecosystem;

其研究内容主要包括区域土地生态系统的完整性和稳定性；