Parts of the following sentence have been given as options. Select the option that contains an error. The teacher asked him not to keep disturbing the class, but it had no affect.

Correct — C. The fault is the confusable pair affect / effect. After 'had no' the sentence needs a noun, and the noun is effect: 'but it had no effect'.

Affect is the verb, meaning to influence — 'the warning did not affect him'. It cannot be the thing the teacher's words lacked.

The other three segments are sound English, so the error sits in option (c).

Why the others are wrong

• (a)
  him not to keep — Ask + object + not + to-infinitive is the standard negative reported request, so 'asked him not to keep' is correct as printed.
• (b)
  The teacher asked — Subject and verb agree, and the past tense asked matches the rest of the sentence. There is nothing to repair here.
• (d)
  disturbing the class, — Keep takes the -ing form, so 'keep disturbing the class' is right, and a comma before 'but' joining two clauses is standard.

CGL error-spotting is usually built on one identifiable rule, and the confusable-word family is a favourite: affect and effect, principal and principle, stationary and stationery.

Effect is the noun for a result. Affect is the verb for influencing something.

Both have a second life — 'effect' as a verb meaning to bring about, 'affect' as a technical noun in psychology — but neither of those readings fits the slot after 'had no'.

Key facts

• Effect is the noun: 'it had no effect'.
• Affect is the verb: 'the noise did not affect her'.
• 'Effect' also works as a verb meaning to bring about, as in 'effect a change'.
• Ask + object + not to + verb is the negative reported request, as in 'asked him not to keep disturbing'.

Common traps

• Scanning for a grammar error and never checking the spelling of 'affect'
• Assuming the segment carrying the comma or the conjunction must be the faulty one

No directly related past PYQ was found.