单元：Module 03.txt

• earth
• moon
• news
• reach
• planet
• yet
• just
• model
• spaceship
• project
• no problem
• latest
• on
• discover
• astronaut
• space travel
• none
• environment
• that
• solar
• system
• solar system
• group
• galaxy
• universe
• Light
• impossible
• out
• communicate