1.
If one thing is added on to another, it is attached to the other thing, or is made a part of it.
Holidaymakers can also ~ a week in Majorca before or after the cruise...
To the rear is a large dining room–added on early this century.
PHRASAL VERB: usu passive, V P n, V-ed P
2.
If you ~ an extra amount or item to a list or total, you include it.
Many loan application forms automatically ~ insurance.
PHRASAL VERB: V P n (not pron), also V n P