1
.
The
scientists
are
trying
to
find
out
the
____________________
of
this
environmental
problem
.
2
.
Twenty
years
after
the
event
,
his
death
remains
a
____________________
.
3
.
The
woman
took
her
boss
to
the
court
because
of
his
____________________
language
in
front
of
her
colleagues
in
the
office
.
4
.
These
drugs
____________________
the
production
of
serotonin
hormones
.
5
.
Some
activities
like
mountain
climbing
and
bungee
jumping
____________________
a
high
energy
state
of
happiness
.
6
.
If
you
don't
know
how
to
____________________
with
the
problem
,
you
can
consult
your
parents
.
7
.
Istanbul
has
an
exceptionally
rich
____________________
of
historic
buildings
.
8
.
Diet
and
exercise
can
influence
a
person's
weight
,
but
____________________
is
also
a
factor
.
9
.
There
are
tests
which
can
establish
a
baby's
____________________
endowment
.
10
.
Children
have
a
natural
____________________
about
the
world
around
them
.
11
.
Police
detectives
____________________
conclusions
studying
the
evidence
.
12
.
Tom's
sister
came
round
on
Saturday
with
her
numerous
____________________
13
.
I
don't
____________________
my
sister
in
any
way
.
Nobody
can
find
out
that
we
are
sisters
.
14
.
Exercise
is
one
of
the
key
____________________
of
a
healthy
lifestyle
.
