After highlighting the fact that it is more important for Surface Structure (SS) than for other levels of Text Base representation (BT) and Situation Model (MS). In this study, we seek to ascertain the degree of certainty for each of these three levels of representation. To do this, we gave to 127 pupils, taken from 3rd and 4th years, material conceived on the principle of phrase recognition, of the analysis of variance applied to the collected results, indicating that pupils are “quite sure” of their answers I. The three levels of representation. But, this degree of certainty is higher for the statements of the SS than for those of the BT and the MS. Older pupils have a higher degree of certainty than younger pupils. The pupils are hesitant, they are "unsure" for the degree of certainty of the answers given to the MS. Also, they should be fully aware of the strategies they have in place to learn, allowing them to constantly evaluate their metacognition, in order to improve their academic performance.
