To clam up means to stop talking
because you are shy or want to
avoid giving away secrets.
Amy clammed up during the meeting
because she was among strangers.
If you tell someone that there are
plenty more fish in the sea, you
are comforting them by saying
that although their relationship
with someone has failed, there
are many other people they can
have relationships with.
Fred is not sad about breaking up with
his girlfriend, because he knows that
there are plenty more fish in the sea.
If you describe a situation as fishy,
you feel that someone is not telling
the truth or behaving honestly.
I suspected something fishy when I saw
him carrying a big suitcase into my office.
A crabby person is unpleasant
It is better to avoid a crabby person
who can spoil your day.
If you say the world is your oyster,
you mean you can do anything or
go anywhere you want to.
You are young, and you have your whole future
ahead of you. The world is your oyster.
Something which is not genuine and
which is intended to deceive or amuse
people by looking like the real thing.
The cod shoes are not comfortable at all.
A red herring takes your attention
away from the main subject or
problem you are considering.
He planted many red herrings among
the clues for the treasure hunt.
A person is described as a shark if he
tricks people by giving bad advice
about buying, selling or investing.
Nobody likes to patronise his shop
because they know he is a shark.