将下列内容段落翻译 A major part of biomass is lignocelluloses.Lignocellulosic material is the nonstarch, fibrous part of plant materials. Cellulose, hemicellulose, and lignin are its three major constituents. Unlike carbohydrate or starch, lignocellulose is not easily digestible by humans. For example, we can eat rice, which is a carbohydrate, but we cannot digest the husk or the straw, which is lignocelluloses.Lignocellulosic biomass is not a part of the human food chain, and therefore its use for biogas or bio-oil does not threaten the world’s food supply.