If
we
all
____________________
environment
-
friendly
,
we
____________________
the
planet
.
If
we
____________________
the
planet
,
it
____________________
.
we
____________________
____________________
,
if
we
pollute
the
planet
.
If
we
____________________
endangered
species
,
they
____________________
____________________
.
we
____________________
have
enough
water
in
the
future
,
if
we
____________________
____________________
it
.