Grammar and Correct Usage
The core concepts
BCS grammar questions test a predictable set of systems: subject-verb agreement, tense and sequence of tenses, articles and determiners, prepositions and prepositional collocations, pronoun reference and case, conditionals, modals, voice, narration (direct to indirect speech), and degrees of comparison. You should also be able to classify sentences by structure (simple, compound, complex) and identify clause types, because questions often ask you to transform rather than merely choose.
Traps that appear in questions
- Intervening phrases. In "The list of items was long," the verb agrees with list, not items. Prepositional phrases, along with, as well as, and together with do not change the number of the subject.
- Indefinite pronouns. Each, every, either, neither, everyone take singular verbs; both, few, many, several take plural.
- Misplaced correlatives. Not only must be followed by but also, and parallel structure must be preserved: "She not only sang but also danced," not "She not only sang but danced also."
- Dangling modifiers. "Walking down the road, a tree was seen" wrongly attaches the participle to tree.
- Tricky prepositions. Comprise takes no of; discuss takes no about; married to, consist of, superior to, prefer to.
- Since versus for. Since marks a point of time, for a duration.
Worked example
Choose the correct sentence: (a) Neither of the boys were present. (b) Neither of the boys was present.
Neither is singular, and of the boys is a prepositional phrase that does not affect agreement. The correct answer is (b).
Rule of thumb
To find the true subject, bracket every prepositional phrase and ask who or what performs the verb. Then check that the verb agrees with that head noun, and that pronouns referring to it match in number.