Gray area
Green with envy
To tell a white lie
To be tickled pink
To be a black sheep
Once in a blue moon
Out of the blue
To have a green thumb
Caught red-handed
Take the red eye
to be very jealous, envious
a late night flight that arrives early in the morning
very rarely
to be extremely pleased
a small lie that is told to be polite or avoid hurting someone’s feelings
to catch someone in the act of doing something
something that is unclear, undefined
to be the outcast, odd one out, unlike the others
randomly, without warning, surprisingly
to be skilled at gardening