The key to successful identification is to find a model structure that is flexible enough to capture the essential features of the system, yet simple enough to be estimated from the available data.
成功辨识的关键是找到一个足够灵活的模型结构，以捕捉系统的基本特征，同时又足够简单，可以从现有数据中估计出来。
The uniformity of the hybrids in the first generation, the dissimilarity in the second, are facts which cannot escape the attention of an accurate observer.
The struggle for survival is the essence of life.
引力波的发现证明了人类智慧和毅力的力量。