Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Esperanto
letero
←
English
letter
(derived)
←
Esperanto
litero
(doublet)
←
Italian
lettera
(derived)
→
Esperanto
litero
(doublet)
→
Esperanto
leterbloko
(affix)
→
Esperanto
retletero
(affix)
→
Esperanto
leterpapero
(affix)
→
Esperanto
leterkesto
(compound)
→
Ido
letro
(borrowed)