A free science workbook with a total of 3700 questions, including 2500 one-question-one-answer questions and 1200 multiple-choice questions. The question-and-answer questions are “biology (basic: cells)”, “physics (basic: general)”, “chemistry (basic)”, “geology/geology (basic)”, “physics (applied/miscellaneous)”, “biology/human body (applied)”. / trivia)” and other 27 fields. Four-choice questions are given in six fields: "Weather / Astronomy", "Animals", "Biology / Human Body", "Plants", "Geo