EAP style: how to be actively impersonal

When people are talking about academic English, one of the features that often gets mentioned is that it tends to be impersonal. Somehow this often gets translated into "it has lots of passives". And although it's true that academic prose does have more passives than most other genres, they still only make up a relatively small proportion of the overall verb forms in any given academic text*. Students (and teachers) can get terribly hung up on the whole passive thing and you can end up with student writing full of awkward, over-engineered passive constructions that just aren't necessary.

But if academic writing isn't just about passives, what is it that makes it impersonal? It's something that's sometimes difficult to put your finger on.

Recently, I spent some time researching how the verb show is used in academic writing - one of those really key academic verbs that sadly doesn't make it onto the AWL because it's too "common". It demonstrates really clearly the differences between everyday language and academic writing.

In everyday contexts, people generally show things to other people:

I want to show people how to cook healthy food.

He showed us his holiday photos.

In academic prose, however, both subjects and objects tend to be non-human:

Research/a study/analysis/a graph shows an effect/difference/pattern/increase etc.

The concept of non-human subjects and objects sounds pretty obvious, but seeing it so simply and clearly demonstrated provided me with one of those light-bulb moments of clarity. I think I can feel a grammar box coming on …

*According to the corpus-based Longman Grammar of Spoken and Written English passives make up around 25% of verbs in academic prose.