At the drop of a hat – instantly
Burn the midnight oil – to work late into the night
Blessing in disguise – something good that isn’t recognised at first
Take with a grain of salt – not take something seriously
Wouldn’t be caught dead – would never do something
A picture paints a thousand words – act more important than speak
Off one’s rocker – delusional
Not playing with a full neck – lacks intelligence
Hit the nail on the head – precise
Cut the mustard – to succeed
