What
can
you
do
if
you
can't
talk
or
walk
?
Stephen
Hawking
has
a
____________________
that
makes
speaking
and
walking
very
difficult
.
But
he
can
still
think
____________________
many
things
.
When
did
the
____________________
begin
?
How
did
it
begin
?
Will
it
____________________
end
?
He
uses
special
machines
to
write
and
speak
.
He
is
known
worldwide
as
one
of
the
greatest
thinkers
of
our
times
.
