Flights can be from volcanic ash.Logical formLearned from5 sentences. (Air traffic chiefs) may warn of a cloud of volcanic ash.Logical formLearned from5 sentences. A volcanic eruption may cause (flight cancellations) by (aviation operators).Logical formLearned from5 sentences. Volcanic ash can be from an eruption.Logical formLearned from5 sentences. A change can be in volcanic activity.Logical formLearned from5 sentences. Air can be volcanic.Logical formLearned from5 sentences. An (ash cloud) may be created by a volcanic eruption.Logical formLearned from5 sentences. A cloud of volcanic ash may move.Logical formLearned from5 sentences. A cloud of volcanic ash may spread across a continent.Logical formLearned from5 sentences. Volcanic ash may drift across a country.Logical formLearned from5 sentences. A volcanic ash may drift from a country.Logical formLearned from5 sentences. A river can be constituted-of-or-filled-with volcanic ash.Logical formLearned from5 sentences. A volcanic rock may be dubbed.Logical formLearned from5 sentences. A volcanic island can be about a size of a US-city.Logical formLearned from5 sentences. Victims of a volcanic eruption can be in a continent.Logical formLearned from5 sentences.