(1) After the 6th century, papermaking spread to Japan and Korea in the east and Europe in the west, which promoted the exchange and development of civilizations. /kloc-In the 3rd century, printing spread eastward to Japan and Korea and westward to Central Asia, Persia and Europe, which promoted the Renaissance in Europe. The compass spread to Arabia and Europe in the13rd century, which promoted the great geographical discovery. /kloc-In the 3rd century, gunpowder spread to Arabia and then to Europe, which promoted the bourgeois revolutionary movement in Europe.

(2) Material 2: Physical remains; Material 3: scientific experiment; Material 4: Documentary records.

(3) "omitted".