Kim Jong-do. 1998. The Study on the Image-Schema Transformations. Studies in Modern Grammatical Theories 12, 141-168. This paper is designed to show an appropriate way to analyse polysemie phenomena by taking a process morpheme. -er as an example. And it emphnsises that their appropriate analysis could be achieved when it is based on the schemathic network categorization model. The model is thought to be able to avoid the problems posed by the traditional categorization and the prototype model. -er is thought to have there contextual meanings: agent, instrument and setting. These meanings can be connected through image-schema transformations. Three schemas which represent their respective meanings can be united through the superschema. On the other hand, the present tense is thought to be polysemous. But its polysemy is caused by transformations applied on another grammatical category aspect. In this point the present tense is not polysemous. This paper also shows that image-schma transformations work on all the grammatical levels, for they are not the superficial grammatical gimmics, but mental activities. Thus all the grammatical phenomena should be analysed ultimately on the base of cognitive activities.