Text-based, expository instructional materials, such as textbooks, even in the beginning of the 21st century, when the dominance of online materials, or computer-based media, television, video, radio, and other new technologies seem to have eclipsed books and print media, still continue to be significant resources for learners at all educational stages for academic purposes (see McGriff 2001). We live in an age when "literacy scholars and practitioners recognize that even films, websites, television programs, ... and even music are simply other forms of 'texts' that communicate and carry meaning to readers" (Hobbs 2001: 45; Halliday & Hasan 1976).
Due to lack of sufficient exposure to the spoken mode of English in an EFL environment, from among the four major language skills--namely, understanding speech, speaking, reading and writing--reading has probably been recognized as the most important skill for foreign-language learners in academic contexts (see Grabe 1991). The importance of reading skill in language learning and language instruction has been to the extent that during a certain period in the history of language learning/teaching, a specific approach under the rubric of "reading approach" emerged which focused on reading as an important tool for language learning (Brown 1994: 44). Today, views on reading theory have changed so dramatically that reading is no longer seen as little more than a reinforcement for oral language instruction. one major advantage of reading, as argued by Chastain (1988), is that language learners can have control over the speed at which they read. A second benefit of reading is that learners can read in their own privacy. This is an important psychological factor for learners who are worried about reciting in front of their peers. Moreover, lack of exposure to the spoken mode of language--especially in a situation such as Iran, where English has got the status of a foreign language in terms of Stern's (1983) categorization--often causes foreign-language learners to resort to the printed form of language, to reading texts, as a compensation for such a shortage.
Therefore, with the inevitable importance of reading comprehension skill, and the unavoidable dependence of EFL learners on reading materials, any effort by the researchers in the field with the intention of facilitating the process of reading or enhancing comprehension of the reading texts by language learners seems to deserve appreciation.
Reading is an interactive skill; it is a process of active and intentional thinking in which meaning is constructed through interactions between the printed page and the reader. The process of meaning construction is influenced both by the text and the reader's prior knowledge (see Anderson & Pearson 1984). Widdowson (1979), however, emphasizes the role of the reader in the process of constructing meaning out of the text to the extent that he believes that meaning does not reside in the text, but rather any text has potential for meaning. Moreover, reading is interactive "in the sense that many skills work together simultaneously in the process" (Grabe 1991: 378). As comprehension is considered the essence of reading; one of the skills required of the reader to better comprehend the content of a text would be recognizing the more important information in the text so that they would be able to summarize the text in their own words or be able to generate questions relevant to the more important points in the text. The two latter abilities, known as metacognitive skills in the literature, have been recognized as generative study strategies (see for example, King 1992; Wittrock & Alesandrini 1990; Tomlinson 1997, 1998; Bonn & Grabowsky 2001). Researchers in the field have come to recognize that the more actively learners get engaged with the reading texts and with the entire learning process, the more they get involved in a process of thinking and development, and the more they are able to relate the content of the reading materials to their own world experience, the more profound their comprehension, recall and retention of the reading materials would be (see for example Anderson 1999).
Furthermore, effective instructional materials that support active learning aim to engage the learners' cognitive processes for meaningful learning, and thereby enable them to read with understanding, or to construct meanings for the texts (Wittrock 1990). A result of information that is made meaningful by the …