A (sleep environment) can be safe.Logical formLearned from9 sentences. An artist may die in sleep.Logical formLearned from9 sentences. A male may awoke from sleep.Logical formLearned from9 sentences. A (sleep paralysis) can be isolated.Logical formLearned from9 sentences. A cause may pertain-to sleep.Logical formLearned from9 sentences. Some phases can be constituted-of-or-filled-with sleep.Logical formLearned from9 sentences. Persons may undergo sleep.Logical formLearned from9 sentences. Sleep can be troubled.Logical formLearned from9 sentences. Persons may go without sleep.Logical formLearned from9 sentences. (Sleep deprivation) can be a problem.Logical formLearned from9 sentences. A (sleep quality) can be subjective.Logical formLearned from9 sentences. (Sleep patterns) can be adolescent.Logical formLearned from9 sentences. Sleep can be erratic.Logical formLearned from9 sentences. (Sleep and dreamings) may pertain-to a band.Logical formLearned from9 sentences. Men may undergo sleep.Logical formLearned from9 sentences.