Economists may scratch heads.Logical formLearned from13 sentences. Persons may scratch.Logical formLearned from13 sentences. A dog may scratch a lot.Logical formLearned from13 sentences. A male may scratch at a back of a neck.Logical formLearned from13 sentences. A hand may be scratched.Logical formLearned from13 sentences. Practical jokes may scratch (card tickets).Logical formLearned from13 sentences. A disk may be scratched.Logical formLearned from13 sentences. A female may scratch nails.Logical formLearned from13 sentences. A sapphire crystal may be scratched.Logical formLearned from13 sentences. A couple may scratch.Logical formLearned from13 sentences. Legs may be scratched.Logical formLearned from13 sentences. A horse may be scratched.Logical formLearned from13 sentences. A female may scratch a back.Logical formLearned from13 sentences. A cat may be scratched.Logical formLearned from13 sentences. Consumers may scratch heads.Logical formLearned from13 sentences.