Complex sentence structures
Control subject clauses, pied-piped relatives, absolute constructions and long noun phrases.
25 minProficiency
1The grammar
A whole clause can act as the subject of a sentence: 'That the policy failed is undeniable.' 'Whether the reform will last remains to be seen.' 'If' cannot replace 'whether' in this subject position. English usually moves a long that-clause to the end and uses 'it' as the subject: 'It is undeniable that the policy failed.'
In formal relative clauses, a preposition can move in front of the relative pronoun: 'the extent to which', 'the theory on which', 'the regime under which'. Quantified relatives follow the same logic: 'three analysts, none of whom had experience'. When a clause such as 'I think' sits inside a relative clause, the pronoun takes its form from the verb it belongs to: 'the candidate who I think was best'.
An absolute construction adds a clause that has its own subject but no finite verb: 'The vote having been taken, the chair closed the meeting.' It is formal and mostly used in writing.
In long sentences, the verb agrees with the head of the subject, not the nearest noun: 'The list of proposals submitted by the offices was sent on Monday.' Quantity expressions are the main exception: 'A number of proposals were rejected.'
2Structure and formation
That- or whether-clause as subject
That/Whether + clause + verb + complement
That prices will rise seems inevitable.
Extraposition
It + verb + complement + that-clause
It seems inevitable that prices will rise.
Fronted preposition in relative clauses
noun + preposition + which/whom + clause
The speed at which costs rose alarmed lenders.
Quantified relative
noun, + some/none/most of + whom/which + verb
The delegates, most of whom were experts, rejected the plan.
Absolute construction
noun + having + past participle, + main clause
The report having been approved, publication began.
3Examples
That the scheme failed surprised nobody.
A that-clause is the subject of 'surprised'.
What the figures imply is open to interpretation.
A what-clause acts as a noun phrase and subject.
Whether the reform will last remains to be seen.
'Whether', not 'if', introduces a subject clause.
It is widely assumed that the ruling will be appealed.
The long clause moves to the end and 'it' takes the subject position.
The regime under which the prisoners were held has since been abolished.
The preposition 'under' comes before 'which'.
The witnesses, most of whom were elderly, gave evidence by video link.
'Most of whom' adds information about the witnesses.
Negotiations having collapsed, the union announced a strike.
The absolute clause has its own subject, 'negotiations'.
4Common mistakes
If the plan will succeed remains unclear.
Whether the plan will succeed remains unclear.
Only 'whether' can introduce this type of clause in subject position.
That the company was at fault it is clear.
That the company was at fault is clear.
The that-clause is itself the subject, so no extra 'it' is added.
The woman whom I believe was responsible has left.
The woman who I believe was responsible has left.
The pronoun is the subject of 'was responsible'; 'I believe' does not change that.
The range of options were narrow.
The range of options was narrow.
The head of the subject is the singular 'range', not 'options'.
5Practical usage
Formal and academic writing
Subject clauses and fronted prepositions allow complex ideas to be packed into one sentence, but extraposition is often easier to read.
Keep the reader on track
When a subject becomes long, check agreement against its head noun and consider moving heavy clauses to the end of the sentence.
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