Stages may pertain-to a collapse.Logical formLearned from6 sentences. A collapse can be swift.Logical formLearned from6 sentences. Restraints may undergo a collapse.Logical formLearned from6 sentences. A (coal mining industry) may undergo a collapse.Logical formLearned from6 sentences. A coal may undergo a collapse.Logical formLearned from6 sentences. An international organization may undergo a collapse.Logical formLearned from6 sentences. (Fish populations) may undergo a collapse.Logical formLearned from6 sentences. Black holes may undergo a collapse.Logical formLearned from6 sentences. A (ceiling collapse) may pertain-to a weekday.Logical formLearned from6 sentences. A collapse may be prefigured.Logical formLearned from6 sentences. An instability may be knowned as (congestion collapse).Logical formLearned from6 sentences. A trench may undergo a collapse.Logical formLearned from6 sentences. Evolution may undergo a collapse.Logical formLearned from6 sentences. Countries may suffer economic collapse.Logical formLearned from6 sentences. Countries may undergo a collapse.Logical formLearned from6 sentences.