Bonjour,
a) If we keep using cars, it will cause more CO2 in the atmosphere.
b) If we produce too much CO2, the fish and coral will die.
c) If we (quel est le sujet ?) don't act now, the planet will be in danger.
d) If lots of people use cars, lots of CO2 will float in the air.
e) If there is not enough rain, this will cause droughts.