Sit in Meaning in English
expression
Definition
To attend a class, meeting, or event as a guest or observer, without being a regular member or participant. Can also mean joining a discussion or group temporarily.
Usage & Nuances
Often used for classes, meetings, rehearsals, or events where you're allowed to observe without fully participating. 'Sit in on' is more common ('sit in on a class'). Sometimes informal. Don't confuse with 'sit-in' (a protest action), which is a separate noun.
Example Sentences
I want to sit in on your class tomorrow.
basic
She was invited to sit in on the meeting.
basic
Can I sit in for a while?
basic
My friend loves music, so he asked if he could sit in with our band practice.
natural
Feel free to sit in anytime if you want to learn more about the project.
natural
During college, I used to sit in on random lectures for fun.
natural