Vocabulary and culture: 10 useful expressions from Shakespeare
Advanced level (C1-C2)

This week we celebrate Shakespeare’s 450th birthday (historians disagree about the exact day) with 10 Shakespearean sayings or sayings that Shakespeare made better known.

catch a cold (get a head cold)
I’m not feeling great. I caught a cold last week and still feel tired.

in a pickle (in a difficult situation or mess)
I really am in a pickle. I don’t know what to do.

foregone conclusion (an inevitable conclusion)
It’s a foregone conclusion that the football manager is going to be sacked for poor results.

in one’s heart of hearts (in your real and honest thoughts)
In my heart of hearts I knew I didn’t really love her.

the green-eyed monster (jealousy)
It was the green-eyed monster that made him do it.

as (good) luck would have it (by fortunate chance)
As luck would have it I found a spare key in my pocket

foul play (dishonest behaviour or violence)
The police ruled out foul play.

to have seen better days (to be old and in poor condition)
The sofa had seen better days.

a tower of strength (someone who gives a lot of support at a difficult time)
My mother was a tower of strength when I got divorced.

tongue tied (not able to speak because of shyness etc)
Unfortunately when he had a chance to speak to the woman he became completely tongue tied.

You can find more at The Phrase Finder