Some frecuently used US slang and idioms. There are so many it was tough selecting which ones to add. However, I didn't want the ppt. to be overly long either. Enjoy :)

1. United States Slang

2. To have guts
guts (1): courage. "It took a lot of guts to ask his boss for
a raise."
This expression replaces the earlier and now obsolete
sense of stomach as “courage,”
a usage from the early1500s. [; late 1800s ]

3. Scarf
Scarf down: to eat very quickly. “He always scarfs
down his food."
1955-60, Americanism; variant of scoff
(to eat voraciously.), with r inserted probably
through r-dialect
speakers' mistaking the underlying vowel as an
r-less ar

4. Airhead
airhead: stupid person. "Believe it or not, Dave can
sometimes act like an airhead!"
Probably used earlier than 1975-80.

5. Screw up
Screw up: to make a mistake. "I screwed up on the
driving test, so I didn't pass.“
Origins aren’t clear.

6. Shades
shades: sunglasses. "Those are really cool shades.”
Shutter Shades were invented in the late 1940s,
became a fad in the early 1980s and has
experienced a revival in the early-to-mid 2010s.
Instead of tinted lenses, they decrease sun
exposure by means of a set of parallel,
horizontal shutters (like a small window shutter).

7. Catch some rays
catch some rays: get some sunshine. "Let's go to the
beach and catch some rays.“
Started being used in the second half of the 1900’s,

8. Bball
shoot some hoops: play basketball. "Let's shoot
some hoops!“
Etymology: based on the basketball meaning of hoop (a
high metal ring through which a ball is thrown to score
points)

9. Cool
cool: excellent;
superb. “English
is totally cool!"
Slang use for
"fashionable" is
1933, originally
Black English,
said to have been
popularized in jazz
circles by tenor
saxophonist
Lester Young.

10. Snookered
snookered: cheated. "I got snookered into buying swamp land in
Florida.“
1885-90; origin uncertain.

11. Couch potato
couch potato: a person who
watches too much television. "Why
did I have to marry such a couch
potato?“
TV was called the boob-tube
because it was thought to be for
dumb people. So, people that
watched it were called tubers. Tom
Iacino used potato as a synonmyn
for tuber and put couch in front of it
since that’s where tubers sit (1976).

12. Geek
geek: someone who works too hard, is
more intelligent than usual, and is
typically but not always unattractive.
"Bill Gates is kind of a geek.“
Perhaps a variant of geck "a fool,
dupe, simpleton" (1510s), apparently
from Dutch gek or Low German geck.

13. Specs
specs: eyeglasses. "I didn't know that you wore specs.“
Short for spectacles, 1807.

14. Get it
get it: to understand something.
"Sorry, but I just don't get it."
Origins not found.

15. Sources
http://www.thefreedictionary.com
http://english.stackexchange.com
http://www.eslcafe.com
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