original: The main techniques concerned are woodcut, engraving and etching, although there are others.
simplifications: The main skills to worry about are woodcut, engraving and etching, but there are others. The woodcut, engraving and etching are slowing down and so are some others. The main techniques are woodcut, engraving and etching. There are many concerns with technique. Some are woodcut, engraving, and etching. The main methods are woodcut, engraving and etching. However, there are others. The main techniques are woodcut, engraving and etching. There are others. The main techniques are woodcutting, engraving, and etching. The techniques of interest are woodcut, engraving and etching. Woodcut, engraving, and etching are main techniques. The primary techniques concerned are woodcuts, engraving and etching, though there are others.