Blue
Black
Green
Silver/Golden
Rainbow!
100
To have the blues
to be sad or depressed
100
black sheep
to be the outcast or odd one in the group
100
To be green with envy
to be very jealous, envious
100
golden opportunity
the perfect chance
100
To show one’s true colours
to show one’s real self
200
Once in a blue moon
very rarely
200
black and white
(of a situation or debate) involving clearly defined opposing principles or issues
*no grey area
200
To have a green thumb
to be skilled at gardening
200
To be born with a silver spoon in one's mouth
to be born into a rich family
200
To colour within the lines
To behave conventionally, to follow the rules
300
Out of the blue
randomly, without warning, unexpectedly
300
to black out
to faint
300
To green-light
to give permission to proceed
300
silver screen
the cinema industry; cinema films collectively
300
With flying colours
to do something very well