The Great Feast and the Sorting Ceremony

I am the hat that's seen them all,

Each and every student to pass through this hall;

I've sorted the great and the good

As well as those of evil mood;

Wear your house colours with pride,

And now let's see where you'll abide;

Ravenclaw with colours bronze and blue,

A house of those clever and studious in hew;

Hufflepuff with colours yellow and black,

A house where friendliness is the knack;

Gryffindor with colours red and gold,

A house of those brave and bold;

Slytherin with colours silver and green,

A house where great power is seen;

So put me on and then you'll see

If your colours are opposite or complementary.