Sentence Structure and Syntax Flashcards

Choose the option that correctly completes the sentence: "Not until the final results were published ___ how badly the trial had been designed."

Answer: did the researchers realise

When a negative adverbial such as 'Not until...' starts a sentence, the main clause needs subject-auxiliary inversion. In the past simple you add the auxiliary 'did' before the subject: 'did the researchers realise'. Options A and C keep normal word order, so they are wrong. Option D does invert, but the past perfect continuous makes no sense for one moment of realisation.

Which sentence uses the introductory participle phrase correctly, with no dangling modifier?

Answer: Having been repaired twice already, the boiler was finally replaced by the engineers.

An introductory participle phrase refers to the subject of the main clause. Only in option C is the subject ('the boiler') the thing that 'had been repaired'. In A the engineers seem to have been repaired. In B the replacement seems to have done the repairing. In D the decision seems to have been repaired.

Choose the correct verb form: "She is one of those analysts who ___ always double-checking their sources."

Answer: are

In the pattern 'one of those [plural noun] who...', the relative pronoun 'who' refers to the plural noun ('analysts'), not to 'one'. So the verb in the relative clause must be plural: 'are'. The plural 'their' confirms this. 'Is' is a common mistake caused by agreeing with 'one'.

Choose the option that correctly completes this pseudo-cleft sentence: "What the committee objected to ___ not the cost but the timing of the project."

Answer: was

In a pseudo-cleft sentence, the 'What...' clause is the subject and counts as singular. It needs a singular linking verb: 'was'. 'Were' wrongly treats the two nouns after the verb as a plural subject. 'Being' is not a finite verb, so the sentence would have no main verb. 'Had' does not work as a linking verb here.

Choose the option that correctly completes the sentence: "___ the storm warning earlier, they would not be stranded on the island now."

Answer: Had they heeded

This is a mixed conditional: an unreal past condition ('earlier') with a present result ('would not be stranded now'). The past condition needs the past perfect, and formal English can invert it by dropping 'if': 'Had they heeded'. 'If they heeded' is a second conditional, which does not fit 'earlier'. 'Should they have heeded' is not a standard conditional inversion. 'Were they heeding' refers to an unreal present or ongoing situation.

Choose the correct relative pronoun: "The candidate ___ the panel believed was best qualified unexpectedly withdrew her application."

Answer: who

'The panel believed' is an inserted clause. Take it out and you get 'The candidate who was best qualified...'. The pronoun is the subject of 'was', so it must be the subject form 'who'. 'Whom' is a common hypercorrection here, because the pronoun seems to sit next to the object of 'believed'. 'Whose' shows possession, and 'which' is not used for people.