App features 1. The materials are arranged in alphabetical order, so you can study according to your English level. 2. You can study reading comprehension (writing, listening), grammar, and vocabulary while solving one problem. 3. Solve the problem and add the words you do not know to the vocabulary book and memorize them separately. 4. Toast function allows you to study words while exiting the app and using other apps. 5. Reading and listening problem solving function added! 6. Added word quiz