level stretch of grade crossing

例句：

1. 1. The student's performance is at a level that is below average.
   学生的表现在平均水平以下。
2. 2. The company's profits have been increasing at a steady level for the past few years.
   公司的利润在过去几年里稳步增长。
3. 3. The temperature has dropped to a level where it feels comfortable.
   温度已经降到让人感觉舒适的水平。