In
the
days
when
roads
____________________
just
made
of
dirt
,
we
often
used
rivers
to
go
from
one
____________________
to
the
next
.
The
Mississippi
River
was
like
a
big
road
that
ran
from
north
to
south
.
____________________
rivers
and
streams
fed
into
the
Mississippi
.
At
times
,
the
river
would
be
____________________
of
boats
and
rafts
.
The
rafts
____________________
float
down
river
.
But
mules
had
to
____________________
some
rafts
back
up
river
.
