These are the most frequently used words in this book.
affluent
air
although
areas
between
billion
case
century
change
china
cities
climate
coal
continue
costs
countries
decades
developing
development
during
earth
economic
electricity
energy
environment
environmental
especially
even
example
fact
fish
food
forest
fossil
fuel
future
global
government
growth
human
important
including
increase
industrial
issues
land
large
less
level
major
market
may
million
nations
natural
needs
new
now
nuclear
number
oil
people
per
percent
plants
policy
political
pollution
poor
population
poverty
power
price
probably
problem
production
public
quality
recent
renewable
resources
should
since
species
states
still
supply
systems
technologies
time
today
two
united
use
vehicles
warming
water
world
years
yet