Climate change is one of the biggest challenges of our time, and we must take action now.
水产养殖的效率不在于生产更多,而在于浪费更少。
善良是一种人人都懂的语言。
我所思念的美人,她在泰山。想追随她,但泰山支脉艰险。侧身东望,眼泪沾湿了衣襟。
我不会满足于次优,我追求更多。
The beauty of instrumental variables is that they allow us to see the world in a new light.