Produce social security cheque sent back in haste regularly by Earl (9)
I believe the answer is:
originate
'produce social security' is the definition.
'originate' can be an answer for 'produce' (thesaurus). I am not sure about the 'social security' bit.
'cheque sent back in haste regularly by earl' is the wordplay.
'cheque' becomes 'giro' (giro is a kind of cheque).
'sent back' shows that the letters should be reversed in order.
'regularly' indicates alternate letters (regularly take one letter, leave next etc.).
'by' says to put letters next to each other.
'earl' becomes 'e'.
The alternating letters of 'haste' are 'at'.
'giro' back-to-front is 'orig'.
'orig'+'in'+'at'+'e'='ORIGINATE'
Can you help me to learn more?
(Other definitions for originate that I've seen before include "Create, initiate" , "Stem" , "pioneer" , "Cause to begin, be the first" , "Bring into existence" .)