Put it at the very end of a scene, after the last line and any door knocking, so the exit closes the moment before a cut to the next shot. Follow it with a reaction sound for the person left behind, then cut to their face.
關於此聲音
This is a short door-closing sound effect, lasting just over a second, built around the solid thud and latch click of a door shutting in one quick movement. It feels abrupt and final, with a dry, everyday snap that lands like a full stop.