Left in Congo with this writer, assess business organisation (12)
I believe the answer is:
conglomerate
'business organisation' is the definition.
'conglomerate' can be an answer for 'organisation' (conglomerate is a kind of organization). I'm not certain of the 'business' bit.
'left in congo with this writer assess' is the wordplay.
'left' becomes 'l' (common abbreviation).
'in' means one lot of letters goes inside another.
'with' means one lot of letters go next to another.
'this writer' becomes 'me' (the person who is writing these clues).
'assess' becomes 'rate' (rating is a kind of assessing).
'l' put within 'congo' is 'conglo'.
'conglo'+'me'+'rate'='CONGLOMERATE'
Can you help me to learn more?
(Other definitions for conglomerate that I've seen before include "Large corporation formed through mergers" , "Coarse-grained rock; large corporation" , "Large company formed by merger" , "Multinational" , "Big diverse firm" .)