There is a very famous example of symmetry in nature - the butterfly. The dotted line down the middle is called ... is called reflective symmetry. It's not just in butterfly wings that you can ...
一些您可能无法访问的结果已被隐去。
显示无法访问的结果一些您可能无法访问的结果已被隐去。
显示无法访问的结果