add
to add a nought

ADD
Attention Deficit Disorder

add in
incluir

add to
an old building added to

add up
it doesn't add up!

add up to
what does it all add up to?

add-on
add-on

fuel
...to add fuel to the fire / to

insult
to add insult to injury, ...

lustre
to add lustre to

oil
to add oil to the flames

sound
to add sound effects to a film

touch
to add a few finishing touches

unnecessary
it's unnecessary to add that...

well
add the sugar and eggs and mix well

zest
to add a zest to