The aim of the present paper is to give a broad picture of the modal verb can, with specific reference to its distribution and uses in contemporary written and spoken British English. I attempted to illustrate that the frequency of the modal verb under scrutiny is strongly dependent on its context, particularly with regard to the diversified occurrence of can. My study investigates this modal auxiliary not in isolation but in combination within a wider syntactic environment, i.e. colligations. The identification of this feature offers an important aid to a better understanding of English; namely to identify what are the natural combinations of the modal can and other grammatical units regarding this modal. The research seeks to arrive at an overview of possible patterns with can, and then account for the way in which usage varies according to contextual influence, syntactic environment, register: written or spoken and meaning of the modality domain. Thus, the modal can is described semantically and syntactically pointing at similarities and differences between the written and spoken Modern English. If its meaning extensions and syntactic surroundings are different, an attempt is made to find an explanation for that.The study is based on corpus material, and data are retrieved from the British National Corpus, which is the largest structured corpus ever compiled. In order to limit the scope of my investigation and find examples for closer scrutiny I chose to observe the data produced by British speakers from 1985. Then I selected 1000 examples in the written and 500 in the spoken with can at random and sorted them into alphabetical order, using both right sort revealing collocations following the modal and left sort – the unit proceeding the modal. Consequently, the present study can be considered as descriptive in nature, making its observations and drawing its empirical basis from authentic uses of the modal can by native speakers. This paper represents an effort to combine the best observations of the earlier studies with new results of my research. The main differences between this and other studies are caused by the difference in perspective (SFG) as well as in the selection of material. Form, meaning and function are all seen as inter-related. SFG with its system of processes and participants has been a useful tool in the analysis of the syntactic environment can occurs in and in distinguishing the meanings and the modality domains of the modal can. Taking the Systemic-Functional model as its basis, the work also draws on other approaches: like appraisal theory and pattern grammar. The current analysis of the modal auxiliary can contributes to the field of corpus based studies through the classification and analysis of a large number of authentic examples of one of the most frequent modal verbs in English and its meanings. This information should be useful to anyone who is interested in a precise description of the modal verb can (dictionaries, electronic corpora and grammars). Acknowledging similarities with other works as to topic and framework the present study has sought to fill the gap in our knowledge of the function and usage of the modal verb can. I hope my investigation helps the students to become aware of the resources which English offers, and which may sharpen their curiosity to extend study of modality to deeper and more specialized works.