Answer:
The way you structure the two sentences depends on how you want the ball to be recognized. Do you want them to know why he is looking at the ball or for another reason? These are important details. I left 4 possible choices below, use whichever one you want.
- "The boy is looking at the ball while it is in the air."
- "The boy is looking at the ball as it is in the air."
- "The boy is looking at the ball since it is in the air."
- "The boy is looking at the ball whilst it is in the air"
