Cambridge Grammar of English Hardback with cd-rom a comprehensive Guide

Processes of change 

340c

The present progressive is used to refer to gradual processes of change:

He’s been in hospital for three weeks but 

is improving steadily.

They’re building a new by-pass. It’ll be good for the town but it

’s taking ages to

finish.

With adverbs of indefinite frequency 

340d

The present progressive is often used with indefinite frequency adverbs such as

always

, constantly, continually and forever to describe events which are regular

but not planned, and often undesired:

I

’m always losing my car keys. I really must get one of those massive big key rings.

I

’m constantly telling the children not to go in there.

She

’s forever doing homework.

602 | Present time

Cambridge Grammar of English

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