理解篇章不僅僅只要讀懂個別的字詞和語句，並且也要能建構一個有關通篇文章的統整模式，稱之為心智模式或者情境模式。在本文的第一部分，我們區分幾種讀者理解文章時會出現的推論：一種是必要性推論（包括局部與整體層次的推論），另一種是可以豐富讀者的理解，但是並非必需的〝單純精緻化〞推論。然後我們接著討論有特定理解困難的兒童問題（界定為他們識字能力達到該有的年齡水準，但是對於篇章的理解能力偏弱）。我們描述這類兒童在回答根據文章進行推論性問題的困難點，並且呈現證據說明這類的困難和理解技能具有因果關係，我們更進一步討論詞彙能力和推論技能的雙向關係。推論技能對於有助於讀者運用的文章脈絡線索推敲出不熟悉字詞的意義；反之，如果讀者具有深度的詞彙知識（即對詞彙所知的一切）與快速提取詞彙的能力，也有助於進行推論。

Understanding a text requires not only understanding the individual words and sentences, but also requires the construction of an integrated model of the text as a whole: a Mental Model (Johnson-Laird, 1983) or Situation Model (Kintsch, 1998). In the first part of this paper, we differentiate between the types of inference that occur as a reader understands a text: necessary inferences (at both the local and global level) and ‘merely elaborative’ inferences, which might embellish the reader’s understanding, but which are not essential to it. We then go on to discuss the problems of children who have a Specific Comprehension Difficulty (i.e. they are able to read words at an age-appropriate level but, nevertheless, have a poor understanding of the text overall). We describe the particular difficulties that such children have in answering inferential questions about a text, and outline the evidence that such difficulties are causally related to comprehension skill. We then discuss the reciprocal relation between vocabulary skills and inference making. Inference skills have a clear role in helping readers to derive the meanings of unknown words from text through the use of contextual cues and, conversely, deep vocabulary knowledge (what is known about words), and rapid access to that knowledge, can support inference making.