extremal graph theory

例句：

1. 1. The temperature reachedan extreme of 40 degrees Celsius.
   温度达到了40摄氏度的极端。
2. 2. The scientist conducted experiments to test theextreme limits of human endurance.
   科学家进行了实验，以测试人类耐力的极限。
3. 3. The company's performance was atits extreme during the financial crisis.
   公司在金融危机期间的表现达到了极点。