单元：WelcomeUnit.txt

• exchange
• lecture
• registration
• register
• sex
• female
• male
• nationality
• nation
• designer
• design
• campus
• formal
• anxious
• annoyed
• annoy
• frightened
• senior
• senior high school
• at last
• outgoing
• impression
• impress
• make an impression
• what if
• guy
• concentrate
• concentrate on
• experiment
• awkward
• junior
• junior high school
• explore
• confident
• confidence
• forward
• look forward to
• take notes
• flash
• flash card
• organise
• organisation
• goal
• strategy
• partner
• improve
• curious
• company
• personality
• style
• revise