英文關鍵字
101
astronomy
basic
class
classes
classroom
classrooms
college
comet
course
courses
discourse
educate
education
educational
elementary
exploration
grade
instruct
instruction
introduction
lecture
lectures
moon
moons
planet
planets
practice
preparation
presentation
pupil
remedial
school
schooling
space
star
stars
student
teacher
teaching
train
training
tutor
type
typewriter
typing
university