Формы обращения в английском языке

Key to the exercise:

a - mum, mummy.
b - caller, nothing.
c - viewers.
d - granddad, grandpa.
e - nothing.
f - ladies & gentlemen.
g - Sir.
h -Your Majesty.
i - nothing.
j - darling, love, dear.
k - listeners.
l - mate.
m - Sir.
n - Madam.
o - officer, nothing.
p - grandma, granny.
q - dear, love.
r - Sir.
s - dad, daddy.
t - nothing.