At B2 level you can understand the main ideas of complex text on both concrete and abstract topics, including technical discussions in your field of specialisation. You can interact with a degree of fluency and spontaneity that makes regular interaction with native speakers quite possible without strain for either party. You can produce clear, detailed text on a wide range of subjects and explain a viewpoint on a topical issue giving the advantages and disadvantages of various options.
You can indicate reservations and reluctance, state conditions when agreeing to requests or granting permission, and ask for understanding of your own position. You can convey degrees of emotion and highlight the personal significance of events and experiences. You can express your ideas and opinions with precision, and present and respond to complex lines of argument convincingly.
Can take an active part in informal discussion in familiar contexts, commenting, putting a point of view clearly, evaluating alternative proposals and making and responding to hypotheses. You can with some effort catch much of what is said around you in discussion, but may find it difficult to participate effectively in discussion with several users of the target language who do not modify their language in any way. You can understand detailed instructions reliably. You can outline an issue or a problem clearly, speculating about causes or consequences, and weighing advantages and disadvantages of different approaches.