常数

例句：

1. 1. The temperature is constant at 25 degrees Celsius.
   温度在25摄氏度时保持不变。
2. 2. The sun's position is constant throughout the year.
   太阳的位置在整个一年中都是固定的。
3. 3.The weather in this region is constant with hot summers and cold winters.
   该地区的天气是恒定的，夏天炎热而冬天寒冷。