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addiction – n. a strong and harmful need to regularly have something (such as a drug) or do something (such as gamble)
complaint – n. a statement that you are unhappy or not satisfied with something
reward – psychology n. Certain neural structures, called the reward system, are critically involved in mediating the effects of reinforcement. A reward is a stimulus given to a human or some other animal to alter its behavior.
originally – adv. in the beginning : when something first happened or began
pretend – v. to act as if something is true when it is not true
abruptly – adv. very sudden and not expected
spontaneous – adj. done or said in a natural and often sudden way and without a lot of thought or planning
excessive – adj. going beyond what is usual, normal, or proper
cautious – adj. careful about avoiding danger or risk
sustainable – adj. able to last or continue for a long time
