句与句之间，保持主题的连贯性是保障段落流畅性的关键。试看以下两例：
1. In this paragraph, boldface indicate topics. Particular ideas toward the beginning of each clause define what a passage is centrally "about" for ,a reader, so a sense of coherence crucially depends on topics/Cumulatively, the thematic signposts that are provided by these icteas should focus the a well-defined and limited set of connected a paragraph from a cumulatively coherent toward. Moving through a paragraph from a cumulatively coherent point of view is made possible by a sequence of topics that seem to constitute this coherent sequence of topicalized idea. A seeming absence of context for each sentence is one consequence of making random shifts in topics; Feelings of dislocation, disorientation, and lack of focus will occur when that happens. The seeming coherence of whole sections will turn on a reader's point of view as a result of topic announcement.
2. In this paragraph, I have boldfaced the topics of every clause. Topics are crucial for a reader because they focus the reader's attention on a particular idea toward the beginningpf a clause and thereby notify a reader what a clause is "about.' Topics thereby crucially determine whether the reader will feel a passage is coherent. Cumulatively, through a series of sentences, these topicalized ideas provide thematic signposts that focus the reader's attention on a well-defined set of connected ideas. If a sequence of topics seems coherent, that consistent sequence will move the reader through a paragraph from a cumulatively coherent point of view; But if through that paragraph topics shift randomly, then the reader has to begin each sentence out of context, from no coherent point of view. When that happens, the reader will feel dislocated, disoriented,out of focus. Whatever the writer announces as a topic, then, will fix the reader's point of view, not just toward the rest of the sentence, but toward whole sections.
在第一段话中，不同的句子频繁地切换主题，所以读起来感觉不够流畅，有断裂感。第二段中，全段围绕少数几个主题，统一贯穿全篇，所以显得更加流畅。
Long sentences may not announce topics often enough or clearly enough to guide us through a multitude of ideas. We need topics as thematic signposts to help us assemble ideas in individual sentences and clauses into cohesive discourse. （连续的长句子之所以难以理解，是因为缺少足够的关于主题的申明）
The secret to a clear and readable style is in the first five or six words of every sentence. （清晰的写作的秘密在于每句话的前5-6个字）
At the beginning of every sentence, locate your reader in familiar territory; at the beginning of a series of sentences, create for your reader a reasonably consistent point of view, a consistent topic string.（每句话以读者熟悉的内容起始（指承接前文），创造连贯的主题）
When that consistent topic string consists of your cast of characters as subjects, and you immediately connect those subjects with verbs that express the crucial actions, you are a long way toward writing prose that your readers will perceive as clear, direct, and cohesive. （当句与句之间保持连贯性的主题，每一句话都使主语和动词与故事的角色和角色的行动向匹配，将极大地有助于写出清晰，直观，连贯的文章）