Servants duke has start to talk with affected manners (10)
I believe the answer is:
downstairs
'servants duke has start to talk with affected manners' is the definition.
I can't tell whether this definition defines the answer.
'duke has start to talk with affected manners' is the wordplay.
'duke' becomes 'd' (abbreviation).
'has' becomes 'owns' ('own' can be a synonym of 'have').
'start to' indicates taking the first letters.
'with' says to put letters next to each other.
'affected manners' becomes 'airs' (I've seen this in another clue).
The first letter of 'talk' is 't'.
'd'+'owns'+'t'+'airs'='DOWNSTAIRS'
Can you help me to learn more?
(Other definitions for downstairs that I've seen before include "towards lower levels" , "On a lower floor" , "in the cellar?" , "On ground floor (or in basement)" .)