The complex sentence with a subject clause 577
§ 150. A subject clause may be introduced by conjunctions (that, if, whether, whether... or, because, the way) or connectives. The latter may be either conjunctive pronouns (who, whoever, what, whatever, which) or conjunctive adverbs (where, wherever, when, whenever, how, why).
Types of subject clauses
§ 151. Complex sentences with subject clauses may be of two patterns:
I. When a subject clause precedes the predicate of the main clause:
What I need is a piece of good advice.
Whether I talked or not made little difference.
Because I ask too many questions does not mean I am curious.
How the book will sell depends on its plot and the author.
That he is a madman in an advanced stage of mania goes without saying.
Whoever moved in next would need it more than I.
Subject clauses of this type cannot be joined asyndetically, as the opening words signal the subordinate status of the clause. The main clause having no subject is deficient in its structure and meaning unless joined with the subordinate clause. Thus the combination of words *is a good piece of advice is neither complete in its structure nor in its meaning without the subject:
What you say is agood piece of advice.
II. When a subject clause is in final position, the usual place of the subject being occupied by formal it:
It seemed unfair to him that he should suffer more than his wife.
It is understood that modern science allows such experiments.
In exclamatory sentences the formal it may be only implied.
How wonderful that they should meet at last! (How wonderful it is...)
In this pattern of the complex sentence the subject clause may be joined asyndetically.