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Griffin was a scientist. Before he started his scientific career, he [had study|had studied|had been studied|studied] biology, chemistry and physics at the university. Griffin was a real genius - he could make anything invisible. He [had conducting|has been conducting|had conduct|had conducted] many experiments with light before he achieved results. He thought that he [should|had to|would|will] get everything he had dreamed about. He wanted to present his discovery to the scientific world, so he made himself invisible. However, in order to take part in the presentation, he [had to|must|could|would] be visible, but he could not do this. He was angry with people because no one [didn't support|supported|had support|support] his experiments, and now he could not return to the real world. His discovery did not serve the benefit of people.