An exchange can be useless.Logical formLearned from6 sentences. (Computer hardware) can be useless.Logical formLearned from6 sentences. A killing can be useless.Logical formLearned from6 sentences. An article can be useless.Logical formLearned from6 sentences. A pawn can be useless.Logical formLearned from6 sentences. Departments can be useless.Logical formLearned from6 sentences. Tools may be rendered useless.Logical formLearned from6 sentences. A rite can be useless.Logical formLearned from6 sentences. Arms may be rendered useless.Logical formLearned from6 sentences. Copies can be useless.Logical formLearned from6 sentences. A display can be useless.Logical formLearned from6 sentences. Sympathy can be useless.Logical formLearned from6 sentences. A response can be useless.Logical formLearned from6 sentences. (Unnecessary one) of surgical procedures can be useless.Logical formLearned from6 sentences. Independent tests can be useless.Logical formLearned from6 sentences.