come in
phr. v.. A1 Beginner Oxford
phr. v.. to enter a room or a building.
phr. v.. to enter a physical space; often used as an imperative or a polite invitation to cross a threshold.
Please come in and sit down.
The teacher told the students to come in quietly because the exam had already started.
As the storm intensified, the hikers were relieved when the innkeeper finally invited them to come in and warm themselves by the fire.
Usage
often used alone as a command or invitation, but can be followed by 'to' and a specific place.
Teaching tip
contrast with 'go in' to show perspective; 'come in' implies the speaker is already inside the destination.
Pitfall
He came in the room.He came into the room.use 'into' when followed by a specific destination; 'come in' is usually used without a following noun phrase.