A boy may be infected with a strain of (bird flu).Logical formLearned from2 sentences. Hunters may be infected by a class of viruses.Logical formLearned from2 sentences. A person may be infected by some viruses.Logical formLearned from2 sentences. Some percent of a population of some countries may be infected.Logical formLearned from2 sentences. Kinds of birds may be infected.Logical formLearned from2 sentences. Cows may be infected with prions.Logical formLearned from2 sentences. Some patients may be infected with a strain of (bird flu).Logical formLearned from2 sentences. Someone may be infected with a (flu virus).Logical formLearned from2 sentences. A virus may infect millions of chicken.Logical formLearned from2 sentences. Chickens may be infected in a country.Logical formLearned from2 sentences. Some chickens may be infected with a variant of a virus.Logical formLearned from2 sentences. A (text book) may be infected by politics.Logical formLearned from2 sentences. Chickens may infect persons.Logical formLearned from2 sentences. A year may infect some persons.Logical formLearned from2 sentences. A cow may be believed be infected with mad disease.Logical formLearned from2 sentences.