Ok so aperently you know nothing of the nazis so to keep m from writng and esssay i'm not going to explian it but a concentration camp is were the nazis used to torture jews and kill them i know a lot more about the nazis than ishould becuase my great great grandad was imprisoned in achwitz and he escaped.
Answer:
This is written in a passive voice and needs to be rewritten in an active voice and reduce length. After 12 weeks had passed, each mouse was randomly placed in one of two treatment groups; in all cases, a die was rolled (was rolled is a passive voice right now) by an experimenter for each mouse, and if it landed on an even number, the mouse was placed in the group that received a pill.
Answer:
When the animals saw that they thought all was lost,
and began to flee, each into his hole, and the birds had
won the battle."
Answer:
Because what you already have isn't ever satisfying enough. It's called adapting, as soon as you get something, you will always crave more. I guess you could call it a psychological addiction.
or
Looking forward to something or pushing for something gives people something to do, and helps you look forward to something later in life.
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I doubt this is correct but I hope it helps a little! :)