English with Isabel
Audit · 7 min7-minute readUpdated 2026-04-25

The 5 errors that flag you as Band 6

Subject-verb agreement, countable vs uncountable, prepositions, word-form confusion, comma splices. The five errors examiners flag most often — small in isolation, signal Band 6 when stacked. Plus the 5-minute self-edit that removes them.

The fastest way to lift your Grammatical Range & Accuracy band isn’t learning new structures — it’s eliminating the five errors examiners flag most often. Each one is small in isolation; together they signal Band 6 even when your ideas are Band 7+. Audit your last essay against this list.

Error 1 — Subject-verb agreement

The subject and verb must agree in number. Plural subject → plural verb. The trap: when the subject is far from the verb, students lose track.

Wrong

  • The number of accidents have risen.
  • One of the students are absent.
  • Each of the children have a book.

Right

  • The number of accidents has risen. (subject = number)
  • One of the students is absent.
  • Each of the children has a book.

Error 2 — Countable vs uncountable

Some nouns can’t be pluralised in English even when they look like they should be. Information, advice, research, news, equipment, furniture, knowledge — all uncountable. No informations, no advices, no researches.

Use much/little for uncountable
much information, little advice, much research.
Use many/few for countable
many studies, few examples, many countries.
Use a piece of / an item of for countable bits of uncountable
‘A piece of advice’, ‘an item of furniture’, ‘a piece of research’.

Error 3 — Preposition mistakes

Wrong prepositions are the single most common Band 6 error. The ones examiners notice most:

depend ON (not depend of/from)
“The result depends on the weather.”
discuss [something] (no ‘about’)
“We discussed the issue.” not “We discussed about the issue.”
good AT (not good in)
“She’s good at maths.”
interested IN (not interested on/about)
“He’s interested in design.”
different FROM (not different than/of)
“The result was different from what we expected.”
consist OF (not consist on)
“The course consists of three modules.”
in / on / at — the time hierarchy
in 2024 (year), in March (month), on Monday (day), on 14 March (date), at 3pm (time).

Error 4 — Word-form confusion

Mixing noun, verb, adjective and adverb forms of the same root. Examiners flag this as a Lexical Resource error, not just a grammar one.

Wrong

  • The economy growth is steady. (using noun as adjective)
  • She is a success writer.
  • This is the most easy question.

Right

  • The economic growth is steady. (adjective)
  • She is a successful writer.
  • This is the easiest question. (one-syllable adjectives take -er/-est, not more/most)

Error 5 — Run-on sentences and comma splices

Joining two complete sentences with just a comma is grammatically wrong in English. Use a period, a semicolon, or a coordinating conjunction.

Wrong (comma splice)

Online learning is convenient, it allows students to study at their own pace.

Three correct fixes

  • Online learning is convenient; it allows students to study at their own pace.
  • Online learning is convenient. It allows students to study at their own pace.
  • Online learning is convenient, and it allows students to study at their own pace.

Spot the error

  1. 1

    Which sentence is grammatically correct?

    Pick one. You'll see why straight away.

  2. 2

    The number of homeless people _____ doubled over the past decade.

    Pick one. You'll see why straight away.

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