approximation of function

例句：

1. 1.The distance between the two cities is approximately50 miles.
   两座城市之间的距离大约是50英里。
2. 2. The error in thiscalculation is approximately 3%.
   这个计算中的错误大约是3%。
3. 3. The temperature differencebetween the two places is approximately 10 degrees Celsius.
   两地的温度差大约是10摄氏度。