An academic is responsible for expanding the boundaries of knowledge. This is serious business and a/an 1) formal writing style reflects the importance and sincerity of this work.  If an academic text contains informal casual language the credibility of the writer is weakened. Therefore, in an academic text you see 2) sophisticated academic vocabulary and words written in their 3) full form. 

Academic writing appears 4) complex because it often refers to abstract ideas, whereas everyday language is more concrete and familiar. Academic subjects have their own
5) specialised vocabulary too which students of other subjects may not be familiar with. Oddly, if English is not your first language, the importance of being 6) concise in academic writing adds to this complexity.  Sentences that are structured around
7) noun phrases are generally 8) concise and clearer than sentences constructed around 9) verbs, but they may be more difficult for students to write. The same is true when writers use sentences that contain subordinate clauses or lists. Sophisticated adverbs and connecting words, and 10) definitions of important words also add to the clarity and precision of academic writing.

An academic paper should be written in an 11) objective style. Academics focus on information and argumentation. In other words, they establish the facts by writing about what they have learned from others and from their own research, and how this has led to new conclusions. This style of writing therefore avoids personal 12) pronouns and the passive voice is a common linguistic feature. Emotional language is also avoided.  Being assertive, and therefore appearing superior and arrogant, is regarded negatively. Writers are expected to be cautious, or tentative, about the conclusions they come to and so 13) hedging is another typical characteristic of academic writing. 

A major part of an academic’s job is to build on the work of others and so it is expected that an author refers to that previous work, hence the need for 14) reporting verbs. It sets the scene for the current research, shows that the author knows his/her subject well, pays respect to previous research and situates the current paper in time and place. This is why the names of other academics occur so frequently in published research papers.  Any idea that is not referenced is assumed to be the author’s idea and so it is 15) unnecessary to write, ‘I think’ or ‘In my view’.