One of the im portant conditions for knowledge to be active Is its generalization. The generalization of knowledge depends on many conditions of the process of acquiring it. Last but not least of these conditions is the co rrect choice of the teaching material, co rrect and illustrative stressing of the ch aracteristic signs of the concepts to be acquired. P ractice has shown that the conception of certain teaching material, which determines the technique of the teacher’s explanation, frequently does not correspond to the substance of actual phenomena; their acquisition then does no. lead to generalization and is nothing but verbal, mechanical recitation. This fact has been found tor instance in the teaching of grammar.
The conception of grammar as an abstract science dealing with the transformation of words and their parts in a sentence irrespective of the meaning of words and ^sentences leads to a one-sided overestimation of formally grammatical signs of concepts. This then leads the pupils to a formal acquisition thereof.
The research carried out by us ascertained the influence of the way of acquisition of grammatical concepts (subject and predicate) on their generalization. Two groups of pupils were under observation. In one of them only the formally grammatical signs were stressed (the so-called grammatical questions). In the second group the semantic sign was mentioned simultaneously, which enabled the pupils to understand the function nnd the relationship of the given concepts in the sentence. The results of the research proved the latter way of acqusltlon to be the mor effective. The research also discovered the causes of various mistakes arising in the acquisition of the subject and predicate and showed how it is possible to eliminate these mistakes.