Most paragraphs are POINT-early, their POINTS typically appearing as the last sentence of their issue. But that is only a statistical observation. We can also put a POINT at the end of a paragraph. （虽然多数情况下，主题句出现在引言部分的最后一句。但这仅仅是一种统计学观察。我们也可以将它放在段落的末尾。）
e.g. Something has happened to the American male's need to display the signs of stereotypical masculinity that once seemed necessary for survival on the frontier. For a long time, American males were confident in their manhood, sure of their sexual roles and images. Indeed, the rugged frontiersmen never even thought about their masculinity; they were simply men surviving in a dangerous world and dressing the part. Then in the nineteenth century, our ideal male became the cowboy, then the world adventurer, then the war hero. They all were confident of themselves and unselfconsciously dressed their part. But in this century, something happened: Hemingway's heroes, for example, seemed to feel that they had to prove that it was still important to be a man among men, and our image of them is one of a kind of Brooks Brothers ruggedness. They seemed less confident that their masculinity had a real function. Now one can detect a new theme: as the male image as conqueror and survivor has lost its value, men have felt free to dress in ways once thought feminine, to wear earrings, even to wear makeup. These signs of a change in the American male's sexual image of himself suggests something deeper than changes in appearance: he is adapting to a world in which the image of traditional masculinity is no longer necessary for survival.
But if the writer does put the POINT sentence at the end of the discussion of the paragraph (or section or document), in its issue he must still use its issue to introduce the discussion in a way that anticipates its topics and themes. （如果作者将主题句放在段落的末尾，那么他必须在引言部分介绍后续将要讨论的关键主题。）
比如上面一段中的首句已经点明了后续讨论的关键主题：
Something has happened to the American male's need to display the signs of stereotypical masculinity that once seemed necessary for survival on the frontier.
Why put a POINT sentence last in a paragraph? Usually, the writer wants to develop her argument before making her claim...But predictably, a writer will put her POINT sentence at the end of the paragraph because she intends to develop, expand, elaborate, explore that POINT in the following series of paragraphs. （为什么作者会将主题句放在段落的末尾呢？通常情况下，是因为作者想在后续段落中展开讨论该主题/论点）