As a kid， I spent my summers with my grandparents on their ranch in Texas. I helped fix windmills， vaccinate cattle， and do other chores. We also watched soap operas every afternoon， especially "Days of our Lives." My grandparents belonged to a Caravan Club， a group of Airstream trailer owners who travel together around the U.S. and Canada. And every few summers， we'd join the caravan. We'd hitch up the Airstream trailer to my grandfather's car， and off we'd go， in a line with 300 other Airstream adventurers. I loved and worshipped my grandparents and I really looked forward to these trips. On one particular trip， I was about 10 years old. I was rolling around in the big bench seat in the back of the car. My grandfather was driving. And my grandmother had the passenger seat. She smoked throughout these trips， and I hated the smell.

一个好的模型应该在复杂性和准确性之间取得平衡，捕捉基本动态而不过度拟合。

We are all haunted by the ghosts of our past.

在林业中，长远眼光不仅可取，而且必不可少。

The city's poor are like the roots of a tree: unseen, but essential to its survival.