英文關鍵字
adult
background
book
bored
casual
caucasian
college
concept
difficult
education
exam
exhausted
expression
fatigue
guy
handsome
hard
head
indoor
learn
learning
male
man
night
one
opened
over
overworked
people
person
portrait
reader
reading
sleepy
smart
stress
stressed
student
study
studying
teenager
textbook
tired
tiredness
university
weariness
white
yawn
yawning
young