将下列段落翻译 While the body of a plant or tree(e. g.,trunk,branches,and leaves)is lignoeellulosic , the fruit(e. g.,cereal and vegetable)is a source of carbohydrate, starch, and sugar. Many plants like canola and mustard also provide fat. The fruit is digestible by humans, but the lignocellulosic body of the fruit tree is not. Some animals, however, can digest lignocellulosic biomass because of special chemicals in their stomach. The use of crops or vegetables for the production of chemicals and energy must be considered carefully as it might affect food supplies.