【思路指点】 说明一种植物,可以从树木、花卉、庄稼等任选一种,一般应介绍它的形态、功用、习性、栽培方法以及种属类别、来源等。不同的植物,特征不同,人们需要了解的内容也不同,所以说明的中心应各有侧重,说明的顺序和方法也应有变化。 比如树木,可以说明它的枝、干、叶等外部形态,再说明功用。说明叶,少不了说明叶的光合作用和呼吸作用。说明外形,应按人们通常的观察习惯,自下而上或由远及近,依空间方位,采用比喻、描写、列数字等方法说明。说明功用,可按先主要后次要的顺序,采用分类别的方法说明。说明叶的光合作用较为复杂,可运 [Reflection Guideline] Explain a plant that can be selected from trees, flowers, crops, etc. It should generally describe its morphology, function, habits, cultivation methods, and species categories, sources, etc. Different plants have different characteristics and people need to understand different contents. Therefore, the center of explanation should be different and the order and methods of explanation should also be changed. For example, trees can explain its external appearance such as branches, stems, and leaves, and then explain the function. Explaining leaves, ultimately, explains the photosynthesis and respiration of leaves. Explain the appearance, according to people’s usual observation habits, from bottom to top or from far and near, according to spatial orientation, using metaphor, description, column numbers and other methods. Explain the function, according to the order of primary and secondary first, using the method of classification. Explain that the photosynthesis of leaves is complex and can be transported