英文關鍵字
bacteria
clean
contaminate
faucet
flow
germ
hand
handwashing
health
hospital
lather
prevent
proper
remove
sink
soap
spout
spread
squeaky
suds
technique
time
washing
water
with
work
英文關鍵字
bacteria
clean
contaminate
faucet
flow
germ
hand
handwashing
health
hospital
lather
prevent
proper
remove
sink
soap
spout
spread
squeaky
suds
technique
time
washing
water
with
work