This work is a continuation of the articles published in the periodical »Pedagogika « (vol. 1956, No 5 and vol. 1957, No 6) dealing with the formation and mastering of the notion of »Subject« from the 4th to the 6th grade of the General Educational School. The aim of this work is to find out the general standard and, above all, the quality of knowledge about the subject and the predicate with pupils leaving the Eight Year School. The method of the research was chosen in such a way as to help unveil those problems which in conventional testing usually remain concealed. First of all a quantitative analysis of an extensive material was carried out (7,164 sentences in which 396 pupils from 12 Prague as well as non-Prague schools were to find the subject and the predicate and underline them), then a qualitative analysis of the material gained by means of individual discussions with 41 pupils, and finally an analysis of the Czech Language textbooks for the 6th, 7th and 8th grade. The methods applied gave us a classified and absolutely concrete look into the selected complex of problems. They supplied documentary proofs demonstrating that the quality of the habit acquired by the pupils was different. They enabled us to characterize this quality in detail separately for each of the three groups of pupils, i. e. those whose general attainment at school was excellent, medium and inferior. In this connection they enabled us to account for the causes of the typical mistakes made by pupils of each of the three categories. These findings allowed us to draw some practical conclusions for the teacher’s work as well as for the exercises in the textbooks. Among other things the demand is being voiced to think over and revise the system of exercises serving to complete the formation of notions and to form habits so as to give the exercises a clear-cut didactic-psychological conception proceeding from the concrete knowledge and the peculiarities of acquiring the given subject-matter and keeping in mind the difficulties that the pupils meet with. Within the framework of the research carried out Jhere stood out the necessity to give special attention to the problems of pupils with inferior attainment, whose knowledge and habits were on a very low level. Pedagogical theory must not by-pass this province if it is to contribute to all pupils, as far as possible, graduating from the Eight Year School and to the largest possible number of our youth completing their secondary education.