A protest where people go into a place — an office, a classroom, a shop, a government building — sit down, and refuse to leave until someone listens to them. The power of it is that it is peaceful and stubborn at the same time. Nobody is fighting; they are just sitting, and the place cannot go on with its normal day. The word comes from the American civil rights movement of the 1960s, when Black students sat at lunch counters that would not serve them and would not get up. Since then students have used it in universities all over the world, and Taiwan knows the shape of it well from the Sunflower Movement of 2014. You hold a sit-in, or stage a sit-in, or students stage a sit-in at the president's office. It is written with a hyphen as a noun; without the hyphen, sit in is a verb phrase meaning something quite different — to join a meeting or class as a visitor, without being a real member of it ("Can I sit in on your Tuesday lecture?"). The -in ending spread to other protest words after this one: love-in, teach-in, be-in.