Good vs Bad Green

Good green
• Green light - go, permission to proceed (with a task)
• The green room - in theater or televisions it is the room where performers and guests go to relax
• Green thumb - good with plants
• Greenback - US dollar bill, money
• Greener pastures - something newer or better (or perceived to be better), such as a new job

Bad green
• Green-eyed monster - jealosy
• Green with envy - jealous or envious
• Green - inexperienced, untested, untrained
• Greenhorn - novice, trainee, beginner
• Green around the gills - pale, sickly