英文關鍵字
20s
academic
adult
attentively
book
campus
casual
caucasian
class
classmates
clothing
college
concentrated
concentrating
education
female
focused
folder
four
frowning
higher
knowledge
laptop
lesson
male
man
mixedrace
notebook
paper
people
school
serious
stern
student
studying
technology
thoughtful
university
unsmiling
woman
young