Types can be abstract.Logical formLearned from3 sentences. (Object types) can be abstract.Logical formLearned from3 sentences. Persons may study abstract (vector spaces).Logical formLearned from3 sentences. An accounting can be abstract.Logical formLearned from3 sentences. Scientific principles can be abstract.Logical formLearned from3 sentences. An units-so can be abstract.Logical formLearned from3 sentences. An (intellectual problem) can be abstract.Logical formLearned from3 sentences. A region can be abstract.Logical formLearned from3 sentences. An abstract thought of books may be concerned.Logical formLearned from3 sentences. A constructor can be abstract.Logical formLearned from3 sentences. A philosophical argument can be abstract.Logical formLearned from3 sentences. Philosophical arguments can be abstract.Logical formLearned from3 sentences. Provisions can be abstract.Logical formLearned from3 sentences. Loyalties can be abstract.Logical formLearned from3 sentences. Inputs can be abstract.Logical formLearned from3 sentences.