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Ongoing processes

The present perfect progressive is not typically used in concluding sections of

academic texts, but may be used to refer to an ongoing process in the discourse up

to a given point:

[discussing the way the playwright, Samuel Beckett, uses the space of the

theatre stage]

This pure space, which has only extension but no location, is quite different

from the theatrical spaces I’

ve been discussing so far.

[embryology lecture]

And probably the surgical procedures that we

’ve been talking about while

thinking of ways of correcting before birth can have a major effect. 

In general, progressive verb forms are not frequent in academic citations and in

the structuring of academic texts (

Û

144e

), since academic texts are usually

concerned with things that have permanent and long-lasting relevance, rather

than temporary or unfolding relevance.