A very studious and intelligent person
Egghead
Be embarassed
Have egg on your face
Someone who watches a lot of TV and doesn't exercise much.
Couch potato
A very durable and robust person; a person who is difficult to deal with.
Tough cookie
Something easy to do
A piece of cake
To risk everything in one person or thing
To put all your eggs in one basket
To remain calm under pressure
As cool as a cucumber
To be extra nice to someone
To butter someone
A good guy or a kind person
Good egg
A person who is a negative influence on others.
Bad Apple
To describe something in only a few words
In a nutshell
Dishonest or undesirable person
Bad egg
A very sensitive matter
A hot potato
Difficult person or thing to understand.
A hard nut to crack
Worry about something that can't be fixed.
Cry over spilled milk
To be in a very difficult situation
(To be) in a pickle
A very important person. A leader (usually about business)
A big cheese
Not to my liking.
Not my cup of tea