英语时差：造纸的化工过程（上）

Most modern paper is made from trees, but that hasn’t always been the case. In fact, paper can be made from any form of cellulose that can be broken down into fibers. Because cellulose is what gives all plants their structure, most plants can be used to make paper. Since the Chinese produced the first true paper around the year 100 A.D., people have made paper with rags, old fishing nets, grass, tree bark, and a variety of other plants. To begin the process, the cellulose has to be boiled, beaten, or shredded into tiny fibers. The paper pulp, made up of those tiny fibers is then spread into sheets, pressed, and dried to make paper. To make strong paper, you need long fibers which is why the pulp has to be beaten instead of chopped. Beating the cellulose separates the fibers from each other, while leaving individual fibers intact.