Common Grammar Mistakes

A2–C1

The errors learners make most often, explained clearly so you can recognize and avoid them.

Lessons in this category

Frequent verb-form errors, and how to fix them.

Mixing up adjectives and adverbs — a very common slip.

When the verb doesn't match the subject — spotting and fixing agreement errors.

Missing, extra or wrong articles — the most frequent article errors.

Wrong or missing prepositions in common expressions.

Choosing the wrong verb pattern after a verb — -ing or to.

Common pronoun errors, from reflexive pronouns to unclear reference.

Treating uncountable nouns as countable, and other countability slips.

Run-on sentences, fragments and other structural mistakes.