E. Green in trouble; she works on machines (8)
I believe the answer is:
engineer
'she works on machines' is the definition.
I can't tell whether this definition defines the answer.
'e green in trouble' is the wordplay.
'trouble' indicates anagramming the letters.
'green'+'in'='greenin'
'greenin' is an anagram of 'ngineer'.
'e'+'ngineer'='ENGINEER'
Can you help me to learn more?
(Other definitions for engineer that I've seen before include "Technician" , "Skilled professional - electrical, civil or mechanical" , "Designer of machines etc" , "Bring about (an event); technologist" , "plan" .)