1) Pear shaped
-After the big argument their Jim and Sally's entire relationship went a bit pear shaped.
-The meeting went completely pear shaped because everyone forgot to prepare for it.
-Tom's final exam went pear shaped because he did not revise the right topics.
Meaning:
If something has gone pear shaped it means it has become a disaster. It might be preparing a dinner party or arranging a meeting, any of these things can go completely pear shaped.
Etymology:
A pear unlike a lot of fruits has a very unique shape, it is not completely round and almost looks like something has gone wrong with the fruit.
2) Twiddling your thumbs
-Everyone in the office was sitting around twiddling their thumbs.
-The boss got angry at me for twiddling my thumbs.
-Sales for the shop were really bad last month which lead to most employees sitting around twiddling their thumbs.
Meaning:
doing nothing.
Etymology:
Both hands are required to twiddle your thumbs so someone who is twiddling their thumbs is not doing anything productive.
3) Spend a penny
-Jenny drinks too much coffee during work, the first thing she does when she gets home is spend a peny.
-Betty needed to spend a penny after her hour long subway ride home.
-Tim went to spend a penny after drinking too much at the bar.
Meaning:
To spend a penny is to go to the bathroom.
Etymology:
It is a very old fashioned expression that still exists today. It comes from the fact that in ladies loos you used to operate the door by inserting an old penny