I hear a knock at the door

Once, twice, three times more

I move forward, my hand on the knob

But when the door opens, the person is gone

I hear a knock at the door

Once, twice, three times more

The opens, no one thereā€¦

I look and stare

I hear a knock at the door

Once, twice, three times more

I rush forward, maybe this time

The door opens nothing but air