About-face = To reverse one's opinion or to change one's mind completely
I decided to return to America for Christmas. After hearing the airfare I did an about-face and decided to stay here.
Optimistic = Hopefulness
Even with all the trouble on Wall Street I am still optimistic about the world economy.
Havoc = Great destruction
The Wall Street crisis has played havoc on the American economy.
Shoddy = Inferior, not made well or not done well
Shoddy workmenship causes production delays and breakdowns.
The king of cool = The sharpest, the best or the most interesting
Apple's new i-phone is the king of cool in the U.S.A.
To be candid = To state perfectly what is on your mind
People who ask for a candid opinion of themselves usually have their feelings hurt.
To forgo = To give up
I have decided to forgo ice-cream to maintain my weight.
Alive and kicking = To be in good condition, to be happy to be alive
Every morning at 4:00 I'm up and alive and kicking.
Giddy vs. glum = Very happy vs. very sad
有頂天。 / 押し黙った。
Supporters of Mr. Obama are giddy while supporters of Mr. Maccain are glum.
Astute = Crafty
He is very famous for his astute way of speaking.