Revolish TOEFL IBT Prep Level 2

Unit 1. Acid Dust
Unit 2. Colors and Emotions
Unit 3. Gold in Alaska
Unit 4. History of the Helicopter
Unit 5. History of the Light Bulb
Unit 6. Jacob Lawrence
Unit 7. James Whistler
Unit 8. Lewis and Clark
Unit 9. The Calendar
Unit 10. Phobias Control the Eyes
Unit 11. Quantum Computers
Unit 12. Stellar Astronomy
Unit 13. Surrealism
Unit 14. The Automobile
Unit 15. The Battle of Gettysburg
Unit 16. The Beginning of the Civil War
Unit 17. The Escalator
Unit 18. The Spanish-American War
Unit 19. Willem de Kooning
Unit 20. The Invention of the Telephone