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7.4 Non-bounding duration adjuncts

These adjuncts have the form of PPs with in or within as head and a temporal NP as complement. They are found in clauses expressing singular achievements or accomplishments:

[23] i The doctor arrived in/within half an hour.  [achievement]

ii They built the house in/within a year.  [accomplishment]

An achievement itself has no duration: the adjunct therefore measures a period that ends at the time of the achievement and begins at the time when it was in some sense set in train or at a time that is a relevant point of orientation in some other way. In [i] the starting-point is likely to be the time the doctor was called. In She reached the summit in two hours the default interpretation is that the starting-point was when she set out on the climb. But it doesn’t have to be: compare We should reach the summit in another two hours. Here we may well have already done part of the climb and I am taking the moment of utterance as the starting-point of the two-hour period.

Accomplishments do have duration, and the adjunct measures that. In a context where the builders have already been working on a house for some months, we would normally use an achievement expression, They will finish building the house in another year, rather than the accomplishment build the house itself. But there may be indeterminacy over the location of the starting-point: the interval could begin with a subinterval that was merely preparatory, rather than strictly part of the building as such.