A model lies regularly, the way things are (2,2,2)
I believe the answer is:
as it is
'the way things are' is the definition.
(I've seen this before)
'a model lies regularly' is the wordplay.
'model' becomes 'sit' ('sit' can be a synonym of 'model'**).
'regularly' means one should take alternating letters (regularly take one letter, leave next etc.).
The alternating letters of 'lies' are 'is'.
'a'+'sit'+'is'='AS IT IS'
(Other definitions for as it is that I've seen before include "In the existing circumstances" , "true to life" , "In the present circumstances" , "Given the position, in the circumstances" , "Actual state of affairs, often contrary to expectations" .)