Complements of comparison and excess
Complements of adverbs are almost exclusively of one type, namely grading. As with adjectives, many adverbial heads admit indirect complements, which depend, not on the adverb itself, but on the degree modifier.
more, less . . . than Bill speaks Spanish much more fluently than his sister.
It rains less often here than in some other countries.
-er . . . than Our coach left earlier than it should have done.
as . . . as I don’t translate as accurately as a professional.
so . . . as …to-infinitive He spoke so fast as to be unintelligible.
too . . . to-inf We reached the castle too late to go inside
not adv enough . . . to-inf We didn’t leave early enough to get there in time.
Such structures may be considered (as with AdjGs) as discontinuous complementation, though the two parts of the structure, before and after the head, differ in position and content. The modifiers more (-er) and less do not necessarily require the than- complement; on the other hand, complements introduced by than cannot be used without a previous modifier which controls this construction.
Adverbs modified quantitatively by so and that are also complemented in the same way as adjectives. The sequence of the clauses can be inverted, the second one then becoming an explanatory comment on the first:
He explained the problem so clearly (that) everybody understood. Everybody understood the problem, he explained it so clearly.
