A book can be on a subject.Logical formLearned from1 525 sentences. A subject can be taboo.Logical formLearned from1 453 sentences. Subjects may pertain-to persons.Logical formLearned from1 438 sentences. A subject may pertain-to a book.Logical formLearned from1 372 sentences. A subject can be subject.Logical formLearned from1 334 sentences. Information can be on a subject.Logical formLearned from1 267 sentences. Subjects can be healthy.Logical formLearned from1 243 sentences. A subject can be controversial.Logical formLearned from1 177 sentences. A subject can be complex.Logical formLearned from1 124 sentences. A subject can be given.Logical formLearned from1 119 sentences. A subject can be difficult.Logical formLearned from1 094 sentences. Persons can be on a subject.Logical formLearned from1 087 sentences. A subject can be interesting.Logical formLearned from1 068 sentences. Subjects can be religious.Logical formLearned from1 023 sentences. A subject can be popular.Logical formLearned from997 sentences.