英文關鍵字
african
age
american
black
board
caucasian
chart
college
concept
diagram
drawing
economics
education
hall
happy
high
hispanic
indoors
international
latin
learn
learning
lecture
lecturer
man
meeting
middle
multiethnic
multiracial
people
person
plan
presentation
scheme
school
showing
sketch
smiling
statistics
strategy
student
study
studying
talking
teacher
tutor
university
white
whiteboard
young