英文關鍵字
adult
back
beautiful
beauty
blackboard
board
boy
business
calculations
caucasian
chalk
chalkboard
cheerful
child
class
classroom
college
communication
concept
draw
easy
education
elementary
explaining
female
formulas
four
happy
kid
knowledge
learn
learning
lesson
math
mathematical
numbers
occupation
one
person
portrait
russian
school
science
smart
smile
standing
student
study
studying
teacher
text
write
writing
young