People showing modern tendency... (7)
I believe the answer is:
inhabit
'people' is the definition.
(people can mean to populate or inhabit)
'modern tendency' is the wordplay.
'modern' becomes 'in' (I've seen this in other clues).
'tendency' becomes 'habit' (I've seen this in another clue).
'in'+'habit'='INHABIT'
'showing' acts as a link.
(Other definitions for inhabit that I've seen before include "Tenant" , "people" , "Dwell in" , "Live in, occupy" , "Occupy - settle" .)