Concepts are mental representation of knowledge. Knowledge and expression of concepts need language. However, just the knowledge of language without concepts also would make the learners successful in careers. This paper discusses the theoretical aspects of formation of concepts and relationship between concepts and language. The learning theories in relation to expansion of concepts are presented. Based on these theoretical aspects, an experimental study was conducted in five phases where a tremendous change in the performance of the students was observed. The phases include expressing the existing concepts (self and surroundings), expansion of concepts through familiar genres, i.e., stories and anecdotes (spiral learning), increasing the pace of expansion through other inputs like news stories and the fifth phase was through academic texts. The performance of the learners after executing the experimental techniques was on par with the other group of students. Hence it can be concluded that the concept expansion techniques would enhance the language proficiency levels of the learners along with knowledge levels.

Concepts are mental categories for objects, events or ideas that have a common set of features. Concepts, in other words, can be called mental representation of knowledge. According to Matlin (1983, p. 176)

A concept refers to making the same response to a group of objects that share similar characteristics.

That is, if the concept of a dog exists, then the features of dog and related terms used to describe a dog form a concept. Thus the entity dog becomes a means for the thought to be carried on (Harre, 2002).

The concepts are mostly identified not with one single feature but with many related features. For example, the concept of "marriage" cannot be defined with one single feature, just a bride or a bridegroom or their living together thereafter; it also involves social approval for their living, a ceremony to bless them, and so on depending on the culture in which it is performed.

Concepts are universal in nature. That is, the concept of "mother", a woman who gives birth to a child, is the same for every person in the world. But the way one understands the activities of a mother and one's expectations from his/her mother can be completely different from one's own siblings. This individual difference is based on one's "schema" which is culture specific and changes from person to person, place to place and religion to religion.

English Studies Journal, Language Learning, Concept Expansion Techniques, Cognitive Development, Conceptual Knowledge, Linguistic Knowledge, Metacognitive Strategies, Language Acquisition, Learning Processes, Developmental Processes, Language Development, Business Management, Proximal Development Theory.