英文關鍵字
boy
caucasian
chemical
chemist
chemistry
child
childhood
children
clever
coat
dangerous
discover
discovery
education
equipment
experience
experiment
eyeglasses
fire
flame
flash
flashing
invention
laboratory
light
little
looking
powder
protective
reagent
research
researching
safety
schoolboy
science
scientific
scientist
sieve
starch
strew
student
study
test
work
worker
young