Bit of trouble cutting grass (10)
I believe the answer is:
smattering
'bit' is the definition.
(I've seen this before)
'trouble cutting grass' is the wordplay.
'trouble' becomes 'matter' (matter is a kind of trouble**).
'cutting' is an insertion indicator (some letters cut their way into a word).
'grass' becomes 'sing' (I've seen this in other clues).
'matter' put within 'sing' is 'SMATTERING'.
'of' is the link.
(Other definitions for smattering that I've seen before include "bit of learning" , "little knowledge" , "Hint" , "Taste" , "Dash" .)