The people who didn't send a present will be called A, B, C and D.
They all got presents.
My plan is to take the presents that they received and send them to you.
Yo four who didn't get presents will be called 1, 2, 3 and 4.

A's present will be sent to 1.
B's present will be sent to 2.
C's present will be sent to 3.
D's present will be sent to 4.