Properties can be useful.Logical formLearned from590 sentences. A discussion can be useful.Logical formLearned from581 sentences. A book can be useful.Logical formLearned from572 sentences. Sources can be useful.Logical formLearned from567 sentences. Materials can be useful.Logical formLearned from565 sentences. An exercise can be useful.Logical formLearned from561 sentences. A site can be useful.Logical formLearned from558 sentences. Guidance can be useful.Logical formLearned from552 sentences. A measure can be useful.Logical formLearned from544 sentences. A feature can be useful.Logical formLearned from533 sentences. Websites can be useful.Logical formLearned from525 sentences. A form can be useful.Logical formLearned from514 sentences. A skill can be useful.Logical formLearned from513 sentences. A reminder can be useful.Logical formLearned from493 sentences. An indicator can be useful.Logical formLearned from474 sentences.