An adverbial clause of manner is a subordinate clause in adjunct function, i.e. modifying the main-clause predicate, and specifying its manner. It bears an adverbial relation to the main predicate analogous to a local or temporal clause. A manner clause S may be paraphrased by a correlative construction of the type ‘so/the same way ... as S’ (a).
An equiparative clause, or comparative clause of equality, is a subordinate clause modifying a dependent of the main-clause predicate, generally an adjectival or adverbial. An equiparative clause S depending on a head A may be paraphrased by a correlative construction of the type ‘equally A as S’ (b).
| . | a. | John worked as his father had worked. |
| b. | John worked as diligently as his father had worked. |
If an English equiparative clause depends on a manner adverbial, it differs from a manner clause only by the presence of this adverbial (b); without it, it would be a manner clause (#a).
Consequently, a manner clause is in a syntactic paradigm with a local and temporal clause ().
| . | a. | John worked where his father had worked. |
| b. | John worked after his father had worked. |
Contrariwise, an equiparative clause is in a syntactic paradigm with comparative clauses of superiority and inferiority ().
| . | a. | John worked more diligently than his father had worked. |
| b. | John worked less diligently than his father had worked. |