long cycle theory

例句：

1. 1.The long-cycle theory suggests that climate change is a slow process.
   长周期理论认为气候变化是一个缓慢的过程。
2. 2. This long-cycle theory has been tested in various experiments.
   这个长周期理论已经在各种实验中得到了验证。
3. 3. The long-cycle theory emphasizes the importance of long-term planning and investment.
   长周期理论强调了长期规划和投资的重要性。