National Learning Corporation has been a leading publisher of test-preparation Passbooks® for more than 50 years, with 6,000 titles available across 22 series. The Graduate Record Examinations are required for admission to graduate school. The GRE General Test measures critical thinking, analytical writing, verbal reasoning and quantitative reasoning skills, while the Subject Tests measure undergraduate achievement in various fields of study. Each study guide contains practice tests consisting of hundreds of multiple-choice questions and answers.