normal flying angle

例句：

1. 1. The normal temperature for this region is around 20 degrees Celsius.
   这个地区的正常温度大约是20摄氏度。
2. 2. He always wears a suit to work, which is quite the normal thing for him.
   他总是穿着西装上班，这对他来说很正常。
3. 3. The normal course of events led to the discovery of the cure.
   正常的发展过程导致了治疗方法的发现。