Colors idioms

go/turn red

blush because you are embarrassed or angry

a red flag

a sign that sth is not right

be like a red rag to a bull

make sb angry

be in the red

be in debt

be red hot

be in high demand

catch sb red handed

find sb doing sth wrong

roll out the red carpet /give sb the red carpet treatment

greet/welcome sth with a lot of respect

feel blue = have the blues

feel sad

out of the blue

unexpectedly

once in a blue moon

rarely (cada muerte de obispo)

be/go green

be environmentally friendly

be green with envy

be very envious or jealous of sb

give/get the green light

give/get permission to do sth

have green fingers (BrE) = have a green thumb (AmE)

be good at gardening

(tell) a white lie

tell a harmless or trivial lie

raise/wave a white flag

surrender or give up

be black and white

be very clear

be in the black

do very well financially