A lot can be about an advance of American civilization.Logical formLearned from6 sentences. Signals can be from alien civilizations.Logical formLearned from6 sentences. A (radio signal) can be from an alien civilization.Logical formLearned from6 sentences. A civilization may undergo a founding.Logical formLearned from6 sentences. Civilization may develop a fine art.Logical formLearned from6 sentences. Competition may occur between civilizations.Logical formLearned from6 sentences. A series can be about early civilizations.Logical formLearned from6 sentences. A person may get from civilization.Logical formLearned from6 sentences. An asian crisis may reduce chances of a clash of civilizations.Logical formLearned from6 sentences. A kind of clash of civilizations may find themselves on sides.Logical formLearned from6 sentences. A road may mean civilization.Logical formLearned from6 sentences. A detritus may pertain-to civilization.Logical formLearned from6 sentences. A civilization may lose an understanding.Logical formLearned from6 sentences. A civilization may gain momentum.Logical formLearned from6 sentences. An industrial civilization may undergo failings.Logical formLearned from6 sentences.