Make sure you knock loudly when you come to the door; I might be in another room, and it is sometimes difficult to hear.
Don't knock so loud, it drives my parents crazy.
There's a strange knocking sound coming from your car engine; you'd better get it checked out.
I
accidentally knocked the milk off the table.
Don't knock something until you've tried it.
The salesman said he could knock ten percent off the price if we decide to buy it today.
He knocked over a lamp as he made his way drunkenly across the room.
The old woman
was knocked down by a car being driven by a young high school student.
I thought I could hear someone in the room but when I knocked at the door, no one answered.
You'll have to knock because our doorbell doesn't work.
We were awakened this morning about 4:00 a.m. by someone
knocking at our bedroom window.
Hey! Be careful; you almost knocked that plant off the table.
There is a Chinese proverb which holds that a clear conscience never fears midnight knocking.
An American football coach once remarked that it's not important whether you get knocked down, it's whether you get up.
Charles Lamb once said "Not many sounds in life, and I include all urban and rural sounds, exceed in interest a knock at the door."