a. Green with envy - To be extremely jealous.
Example: "When she saw his new car, she turned green with envy."
b. Black sheep - An outcast or someone who is different from the rest of the family or group.
Example: "He's the black sheep of the family; everyone else is successful."
c. Red flag - A warning sign or signal of potential danger or problem.
Example: "His aggressive behavior is a red flag; we need to be cautious."
d. Golden opportunity - A chance or opportunity that is highly advantageous.
Example: "She saw the job opening as a golden opportunity to advance her career."
e. Paint the town red - To go out and enjoy oneself, usually by partying or celebrating.
Example: "It's my birthday; let's paint the town red tonight!"