Corpus quantitative approach in teaching, which is of growing interest, entails some revision of the L2 vocabulary selection procedures and provides solutions for a wide range of practical problems. The focus throughout is on the discussion of research on the quantitative and qualitative characteristics of language which both teaching content and language acquisition practice could draw on. This research regards human language as a rank distribution, which has serious implications on quantitative aspect of learner’s vocabulary. We also looked into the ways to factor in the data from a small professional discourse corpus in order to target the units that have the greatest statistical prominence. Both BNC and our own collection of texts are explored. The study also elaborates on academic writing cohesive devices and grammar patterns introduction, which is approached through concordancing corpus strings to (i) provide frequency evidence and (ii) introduce a contrast in usage in various corpus genres. Striking differences that are evidenced by the frequency lists could be related not only to register, but also to the choice and instances of academic cohesive clusters which are favoured by the apprentice writers and the expert writers. With the aim of capitalizing on corpus approach a number of small-scale corpus research tasks were developed. This study also uses corpus tools and data to give a seemingly subjective phenomenon of hedging some quantitative measurement. While experimenting on corpus in the classroom, the attention of learners was drawn to various means of hedging, such as lexical bundles or down-toners that manifest themselves as important communicative strategies. Thus, corpus was used to inform both the language instructor and the student in the classroom to look in detail at differences in the use of lexical and grammatical units in different varieties of language, address contrasting register variations, and readily provide contemporary professionally relevant examples of actual language usage. It has to be noted that university students have a tendency not to perceive register violations as language errors on a par with those of grammar, lexis or punctuation. Hence, corpus investigation as raising awareness tool also proved to be an effective teaching material generator. Nowadays syllabi have the opportunity to be rather sensitive to the quantitative evidence that corpora offer us; what is more, as a result of this study, we would conclude that university students are responsive to the small-scale investigation of register differences, lexico-grammatical frequency and patterning, which have been brought directly into the L2 classroom.