悲伤的

Dragon heartstring, so Harry, Ron and Hermione unite the three Ollivander wand cores (other wandmakers may use different substances, as shown by Fleur's wand, but Ollivander is widely acknowledged to be the best maker).

龙心弦。于是哈利、罗恩和赫敏集合了奥利凡德的三种杖芯（其他魔杖制作者会使用不同的材料，正如芙蓉的魔杖，但奥利凡德被公认为是最好的）。

The collaborative activities of the military decision making are variable and complex.

联合作战要求参战各方克服组织、经验、资源和技能的差异，共同协作。