A sword can be formidable.Logical formLearned from6 sentences. Teacher-tyrants can be formidable.Logical formLearned from6 sentences. An author can be formidable.Logical formLearned from6 sentences. A barbour can be formidable.Logical formLearned from6 sentences. Difficulties of preparring a force can be formidable.Logical formLearned from6 sentences. Restrictions can be formidable.Logical formLearned from6 sentences. Requirements can be formidable.Logical formLearned from6 sentences. A birch-tree can be formidable.Logical formLearned from6 sentences. (Security forces) can be formidable.Logical formLearned from6 sentences. Cliffs can be formidable.Logical formLearned from6 sentences. A (staying power) can be formidable.Logical formLearned from6 sentences. Lines can be formidable.Logical formLearned from6 sentences. Women can be formidable.Logical formLearned from6 sentences. A (work ethic) can be formidable.Logical formLearned from6 sentences. Mothers can be formidable.Logical formLearned from6 sentences.