The room in which the glass looks like a mirror is kept very brightly lit, so that there is plenty of light to reflect back from the mirror's surface.
(the glass; looks; like a mirror; L:The room) (The room in which the glass looks like a mirror; is kept; ) (The room in which the glass looks like a mirror; very brightly lit; ) (plenty of light; to reflect; back from the mirror's surface)
the glass The room in which the glass looks like a mirror The room in which the glass looks like a mirror plenty of light
looks is kept very brightly lit to reflect
like a mirror L:The room
back from the mirror's surface