我们的祖先在古代的四大发明闻名于世。除此之外，还有许多居世界之最的发明创造：（1）陶瓷器。在7800年前北渭水、任水流域的先民就已经开始烧制红、灰色多种形状的陶瓷器具了。（2）太阳能利用开始于3000年前。（3）铸造。我国在古代就开始利用泥灌、铁灌、蜡谁这三大铸造方 Our ancestors are famous in the ancient four great inventions. In addition, there are many of the world’s most inventions and innovations: (1) ceramics. Before 7800 years ago, the people of Beiwei River and Renshui River Valley started to burn red and gray ceramic ware of various shapes. (2) Solar energy utilization began 3000 years ago. (3) Casting. In ancient China began to use mud irrigation, iron irrigation, wax who the three casting side