Unlucky actor may struggle to remember them (4,5)
I believe the answer is:
hard lines
'unlucky' is the definition.
(both might be said to express sympathy)
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for hard lines that I've seen before include "Tough" , "Script full of tongue-twisters?" , "Bad luck" .)