- black sheep [usually singular]
A person who is different from the rest of their family or another group, and who is considered bad or embarrassing.
the black sheep of the family
- do somethign till you are blue in the face (informal)
to try to do something as hard and as long as you possibly can but without success
You can argue till you're blue in the face, but you won't change my mind.
- red-letter day
an important day, or a day that you will remember, because of something good that happened then. It's from the custome of using red ink to mark holidays and festivals on a calendar.
birthdays, wedding anniversaries and otehr red-letter days
- white as a ghost [of some one]
extremely pale, as if frightened.
My sister became white as ghost when she saw the man at the window.
- with flying colors
with great success.
She took a driving test and passed with flying colors.