Lines in, for example, witty remark (5)
I believe the answer is:
sally
'witty remark' is the definition.
'sally' can be an answer for 'remark' (sally is a kind of remark). I am not certain of the 'witty' bit.
'lines in for example' is the wordplay.
'lines' becomes 'll' (two abbreviations for line).
'in' means one lot of letters goes inside another.
'for example' becomes 'say' ('say' can be used to introduce an example).
'll' going inside 'say' is 'SALLY'.
Can you help me to learn more?
(Other definitions for sally that I've seen before include "- - Lunn, flat cake" , "excursion" , "army" , "Charge" , "Sarah might make a witty remark about the willow" .)