Catt concept

例句：

1. 1.The concept of sustainability is crucial forthe development of a green economy.
   可持续发展的概念对于绿色经济的发展至关重要。
2. 2. The new concept ofeducation has revolutionized the way we learn.
   新教育理念已经彻底改变了我们学习的方式。
3. 3. The concept of time is fundamental tounderstanding the passage of time.
   时间的概念是理解时间流逝的基础。