A
____________________
is
an
instrument
that
makes
work
easier
.
____________________
machines
often
have
one
or
two
parts
.
____________________
machines
have
more
than
two
parts
.
The
earliest
writers
used
a
tool
such
a
knife
to
write
on
____________________
____________________
.
Much
later
they
began
to
use
papers
.
Then
in
a
town
in
Germany
around
____________________
.
.
.
A
man
called
Johannes
Gutemberg
invented
the
____________________
____________________
.
It
was
a
____________________
revolution
.
The
steam
engine
was
invented
about
____________________
years
ago
.
The
steam
machine
used
the
steam
from
____________________
water
.
It
was
part
of
the
Industrial
Revolution
and
also
a
____________________
Revolution
.
The
____________________
was
invented
about
170
years
ago
and
started
a
communication
revolution
.
The
telephone
was
invented
about
____________________
years
ago
.
