英文關鍵字
answer
ask
background
black
blackboard
board
bubble
center
chalk
chalkboard
class
communicate
communication
concept
data
drawn
educate
education
faq
help
helpdesk
icon
idea
illustration
info
inform
information
informative
internet
knowledge
learning
letter
logo
many
pattern
question
ring
school
search
service
set
sign
speech
study
support
symbol
table
template
text