英文關鍵字
3d
advanced
app
application
background
beginner
black
business
button
college
commutation
commutator
concept
course
design
education
element
elementary
english
flag
foreign
icon
improve
interface
intermediate
internet
interpreter
knob
knowledge
language
learn
lesson
level
multilanguage
national
online
professional
proficiency
school
schooling
selector
skill
speak
switch
technology
test
translate
translation
translator
web