+291.+ Words that are ordinarily used as nouns, are sometimes used as
adverbs. These are the nouns that denote time, distance, measure of
value or direction. They are added to verbs and adjectives to denote the
definite time at which a thing took place, or to denote the extent of
time or distance and the measure of value, of weight, number or age.
They are sometimes used to indicate direction. For example:
They were gone a _year_.
He talked an _hour_.
They will return next _week_.
They went _south_ for the winter.
They traveled 100 _miles_.
The wheat is a _foot_ high.
The man weighed 200 _pounds_.
In these sentences, the nouns, _year_, _miles_, _hour_, _foot_, _week_,
_pounds_ and _south_ are used as adverbs. Remember every word is
classified according to the work which it does in the sentence.