求翻译：一些较大的群体性事件往往都是经过了事先周密的策划，目的比较明确，行动十分统一，甚至出现跨地区、跨行业的串联活动。是什么意思？

Some of the larger group events tend to be the result of careful planning in advance, purpose clearer, very unified action, there is even a trans-regional, cross-line activity.