English9 min readUpdated 2026-09-16

Top 50 Grammar Rules for Error Spotting in SSC CGL & CHSL

Error spotting questions do not test random grammar. They test the same 50 recurring rules. Master the top 15 most frequent grammatical traps here.

Preparation Guru Academic TeamEnglish Language & Linguistics

Rule 1 to 5: Subject-Verb Agreement Traps

1. When two subjects are joined by 'as well as', 'with', 'along with', 'together with', 'accompanied by', 'in addition to', the verb agrees strictly with the FIRST subject.

Example: 'The captain, along with all his sailors, was (not were) rescued.'

2. When two subjects are connected by 'Neither... nor', 'Either... or', 'Not only... but also', the verb agrees with the NEAREST subject.

3. 'One of the' is always followed by a PLURAL noun, but a SINGULAR verb (unless preceded by a relative pronoun 'who/which').

Key Strategy Takeaway

Identify the true grammatical subject; ignore parenthetical prepositional phrases separating subject and verb.

Rule 6 to 10: Inversion & Correlative Conjunctions

4. When a sentence begins with a negative adverb ('Hardly', 'Scarcely', 'Rarely', 'Seldom', 'No sooner'), auxiliary inversion is mandatory (Auxiliary verb precedes Subject).

Hardly / Scarcely is paired with WHEN (not then/than).

No sooner is paired with THAN (not when).

Example: 'No sooner had I reached the station than the train departed.'

  • 'Lest' is always followed by 'should' or base subjunctive (never 'will' or 'not').
  • 'Although / Though' is paired with 'yet' or a comma (never 'but').
  • 'Between' is followed by 'and' (never 'to').

Rule 11 to 15: Conditionals & Hypotheses

5. Unreal Past / Third Conditional: 'If + Past Perfect (had + V3), ... would have + V3'.

Example: 'If you had studied consistently, you would have cleared the exam.' (Never 'If you would have studied').