Be sad to see me out of work (4)
I believe the answer is:
mope
'be' is the definition.
(I know that mope is a more specific form of be)
'me out of work' is the wordplay.
'out of' indicates putting letters inside (some letters on the outside of others).
'work' becomes 'op' (abbreviation for opus).
'me' enclosing 'op' is 'MOPE'.
'sad to see' is the link.
This may not be right. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for mope that I've seen before include "Feel dejected and listless" , "Languish" , "Move around slowly and aimlessly" , "Poem (anag.)" , "Yield to low spirits with an odd poem" .)