ray
加入词篮X-ray
reflection
reflect
laser
focus
vibrate
quake
interference
interfere
echo
wave
frequency
period
microwave
short-wave
radar
potential
voltage
resistance
volt
conductor
conduct
semiconductor
pressure
stress
strain
mass
keep
stay
retain
variety
species
rare
energy
power
contaminate
pure
sheer
environment
preserve
conservation
protect
protection
protective
wildlife
pollute
pollution
resource
renew
recycle
reproduce
acute
sustainable
sustain
erode
erosion
greenhouse
lead
stack
exhaust
ethnic
native
evolution
evolve
primitive
civilize
civilization
civilization
civilise
cultural
culture
decent
respect
fierce
bow
arrow
stick
origin
original
source
tradition
traditional
convention
conventional
usage
antique
conceal
dig
ruin
sacrifice
language
idiom
dialect
accent
