knock

Everyday

1. To hit a door or window with your knuckles so people inside hear you. tree →
2. To hit something by accident so it moves or falls: knock over a cup. tree →
3. To hit or bump a part of your body: knock your knee. tree →
4. A noun: the sound of knocking, or a hit or bump. tree →
5. Knock down: to make a building or a person fall to the ground; knock out: to make someone unconscious or to beat a team so it leaves a competition. tree →

In the lessons

Everyday manners: knock before you go into someone's room. Safety: a knock on the head should be told to an adult; don't open the door to a knock if you are home alone. In stories a knock at the door means someone has arrived and something will happen. Jokes: «knock knock» jokes. Phrases: knock on the door, knock over, knock down, knock out, a knock on the head, knock it off (stop it), knock-on effect.

Examples

• Please knock before you come into my room. tree →
• There was a loud knock at the door. tree →
• I knocked over my juice and it spilled everywhere. tree →
• She knocked her elbow on the table. tree →
• They knocked down the old shed to build a playhouse. tree →
• Our team got knocked out of the cup in the semifinal. tree →
• If you get a knock on the head, tell a teacher. tree →
• Knock knock! Who's there? tree →
• The wind knocked the bin over. tree →
• He knocked at the door--tap, tap. tree →

Note

The k is silent: say «nock». Regular verb: knocked. «Knock knock» starts a joke game. «Knock it off» is a casual way to say «stop it». Not used in maths for numbers, except a team knocked out leaves fewer teams in the competition.