Give rough treatment to new worker he takes in
I believe the answer is:
manhandle
'give rough treatment to' is the definition.
(I've seen this before)
'new worker he takes in' is the wordplay.
'new' becomes 'n'.
'worker' becomes 'hand' (hand is a kind of worker).
'he takes' becomes 'male' (I can't justify this - if you can you should believe this answer much more).
'in' indicates putting letters inside.
'n'+'hand'='nhand'
'nhand' placed within 'male' is 'MANHANDLE'.
Can you help me to learn more?
(Other definitions for manhandle that I've seen before include "Treat roughly, or move by human effort alone" , "Push (someone) about roughly" , "Mistreat" , "Give rough treatment to" , "Knock around" .)