The present thesis is a corpus based contrastive study. It is devoted to the polysemy of the verb think. The cognates English think and Norwegian tenke are both frequently occurring verbs which express different meanings in various syntactic environments. One of the aims of this research is to find out to what degree think corresponds to tenke. In other words how often the Norwegian verb tenke is used as a translation of its English cognate think.The Norwegian verb tenke has developed a number of meaning extensions and can form the multi-word verbs, but whether these are the same as those of think will be revealed in the course of the investigation on the basis of 985 examples extracted from the ENPC. If it appears that the two verbs have developed different meaning extensions and that there is no translation correspondence at all, an attempt will be made to find an explanation for that.The verb think is used as a mental verb of Perception and Cognition. An attempt will be made in order to find out whether the same is true of the Norwegian verb tenke.Think is also used as a part of a Discourse Marker. Is the degree of its meaning used as such the same/not the same/slightly different dependent on where in the sentence it occurs: in the initial, medial or final position of the sentence? An attempt will be made to find it out.As the study of the Norwegian verb tenke is just as enormous and time consuming as the present study of the English verb think; it is beyond the scope of this research. The meanings of the verb think will be studied on their own and also in relation to their Norwegian translations. The Norwegian cognate tenke will be analyzed not in general, but to an extent relevant for this thesis. That is why the scope of attention will not be distributed equally between the two verbs.It is necessary to specify here that I will look only at translation from English into Norwegian so that tenke will be studied only to the extent that it translates think. The thesis is organized as follows: After all 985 examples have been extracted from the ENPC and stored in FileMaker Pro 5.5., they are classified according to SFG criteria into process types. Since the verb think is most frequently found to express Mental Process, discussed in chapter 2., a considerable amount of analysis is done here. It is subdivided into two sections, which discuss Mental Process Perception (section 2.1.) and Mental Process Cognition (section 2.2). Chapter 3 is devoted to the Interpersonal and Textual functions of the verb think. It is additionally subdivided into section 3.1. I think as a Discourse Marker, 3.2. Position of the Discourse marker I think in the sentence, 3.3. The Discourse marker I think and Face-factor, section 3.4. Differences and similarities regarding Face-factor in different cultures. Chapter 4 summarizes the main results of the investigation.