Wind is a __________ resource—it never runs out.
hidden
regular
dangerous
renewable
Scientists are working hard to __________ turbines more efficient.
show
turn
push
make
Wind was used to move sailing ships across the oceans and to __________ machines like windmills.
fix
drive
break
power
Turbines must be placed in locations where wind is strong and __________.
steady
cold
noisy
sunny
Wind energy may not __________ all of our problems.
fix
explain
break
solve
Now we use it to __________ electricity.
protect
share
sell
generate
It does not produce __________ gases or harm the environment.
harmful
deep
strong
colorful
It’s difficult to __________ the electricity to where it is needed.
protect
discover
deliver
remove
Some people say turbines spoil the __________ of natural places.
beauty
history
safety
weather
In the future, it might help us __________ a healthier planet.
build
save
test
control