《杨树》是一篇以客观实体为对象的说明文。这篇说明文对我国最常见的树种——杨树的有关科学知识都一一作了简明扼要的介绍说明,不但语言通俗,概念明确,内容具体,而且说明逻辑条理,结构层次分明。在内容安排上,本文是先“定义”后“解说”,在“解说”部分,是先“种类”再“特点”后“用途”,分层依次写来;在材料处理上,是先“总”后“分”再由“分”而“总”,条分贯综,一脉相承,使整篇文章的重点得以突出。全文九个自然段,依据内容 “Poplar Tree” is an expository text based on objective entities. This expository article provides concise descriptions of the most common species of trees in China—the scientific knowledge of poplars. It is not only language-plain, concept-specific, and content-specific, but also logically structured and structured. In terms of content arrangement, this article is “definition” followed by “commentary”. In the “interpretation” part, it is the “kind” and then “characteristic” and “use”, which is written in layers; in terms of material processing, it is first.“ The total ”after“ points are divided into ”points“ and ”totals", and the scores are divided into different lines and they all come together in one continuous line, so that the focus of the entire article is highlighted. Full text of nine natural paragraphs, based on content