Seek answers to riddles

There is no war between east, west, north and south. The name of the village is a corner in the north, only in the north. In addition, the Northern Expedition and Beidou are both possible.

Summer has passed. Farewell is the autumnal equinox in the solar terms. It's autumn in Xia Hou, and parting is one minute.

Gold, silver, iron and tin are all difficult to use as plaques.