1) requirements: see here Reading section: 50 multiple-choice questions Mathematics section: 50 multiple-choice questions Writing section: 2 essays 2) time duration 4 hours for 1, 2, or all 3 sections. You can give 1 section at a time (4 hours) or 3 sections in one seating (4hours) 3) what's the eligibility: i think anyone with high school or maybe nothing specific required. 4) exam preparation can use study guides. like pearson, cliffnotes. I bought cheap from ebay. some from library. writing requires more practice and the essays need to be above american high school standards. practice a lot. 5) can h4 take this exam? yes. sure. All the best!