A.
Example,
While John was lying on his bed, Jack was outside playing soccer.
Well you can use it then explain how you think it fits in like a plot for example you could use it to explain their feelings and what was happening
Water;the most important thing on earth, we use it to survive. Though there is not much of it to drink, there is a bunch of salt water. If we do not have water we will die. ( please don’t use this, it’s late and I wanna help so just use the idea, not the paragraph)