to become larger in number, amount or degree
increase/ go up/ rise
to be less and less difficult to do or understand
get easier
to be more and more difficult to do or understand
get harder
to become less or go down to a lower level
decrease/ go down/ fall
to make (something) smaller or less in size, amount or price
reduce
to make something better, or to become better
improve
to become more unpleasant, bad or severe
get worse
self-driving
driveless
all the people who live in a particular area, city or country; the total number of people who live there
population
the process of making air, water, soil, etc. dirty
pollution
a source of power, such as fuel, used for driving machines, providing heat, etc.
energy
