This study assumes that linguistic structure plays a significant role in comprehending sentences and texts. It also assumes that the process of learning requires inferences to make connections across and within the local and global discourse contexts. To establish these connections, there is a need of integrating information from prior content of discourse and knowledge or from the reader's schemata to build a coherent memory that represents the events and concepts which describe the texts. To that end, the paper reviews studies on depth-first versus breadth-first models, adopted by the parsers, which address the linguistic structure in sentence and text comprehension. It further examines how the readers’ or listeners’ long-term memory and mental models affect the sentence and text comprehension. The findings of the study show that vocabulary depth and breadth are two important constructs to consider while assessing higher-level processing of reading comprehension. It also shows that having a comprehensive understanding of the gradations of the meaning of a word in a variety of contexts will permit the readers to develop a better understanding of the text, and in turn, to better express themselves.