Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Luxembourgish
hëllefen
←
German
helfen
(cognate)
←
English
help
(cognate)
←
Proto-Germanic
*helpaną
(inherited)
←
Old High German
helfan
(inherited)
←
Icelandic
hjálpa
(cognate)
←
Dutch
helpen
(cognate)