Raining cats and dogs
Raining very heavily
The apple of my eye
Someone special and loved
Hit the books
Study
Better late than never
It's good you came, even if you're late
Keep your head up
Stay positive
Hold your horses
Be patient, wait
Couch potato
A lazy person
Pass with flying colours
Do very well
All in the same boat
In the same situation
Out of the blue
Suddenly, unexpectedly
A little birdie told me
I heard a secret/rumour
Not my cup of tea
Not something I enjoy
Teacher's pet
The teacher's favourite student
At the eleventh (11th) hour
At the last possible moment
A pain in the neck
An annoying person or thing
The black sheep of the family
Bite off more than you can chew
To take on too much/more than you can handle
Hit the nail on the head
Said exactly the right thing
Rome wasn't built in a day
Important things take time
On cloud nine
Let sleeping dogs lie
Don't talk about old problems, leave them alone
Cry over spilled milk
Don't be upset about something that can't be changed
Back to the drawing board
A blessing in disguise
Something that seems bad but turns out good
Burn bridges