Evidence-based answer · Last updated · How it’s made
English articles ("a/an" and "the") are hard for L2 learners mainly because they encode abstract meanings (definiteness, specificity, whether something is being introduced as new or already known) that many languages don't mark with separate little words at all, so learners from article-less languages have to build a whole new mental category almost from scratch. On top of that, articles are short, unstressed, and easy to skip in speech, and English's own rules for when to use "the," "a," or nothing are riddled with exceptions, so even learners whose native language does have articles, or who reach advanced/near-native levels, keep making errors.
Answered for language learning in general. No specific language was set for this question, so the findings are drawn from general second-language research rather than one language’s literature.
Speakers of languages without articles (like Korean, Russian, or Japanese) tend to use "the" not just for things already known to the listener (definiteness) but also for things the speaker has a specific person or thing in mind about (specificity), leading to systematic overuse of "the" with specific indefinite nouns like "a certain book.1,2,11
In plain terms
Example
The way learners misuse articles isn't random or purely copied from their native language; researchers argue learners are drawing on a small set of possible meaning-systems that appear to be built into how humans process language in general, sometimes called Universal Grammar.1,2,5,11
In plain terms
Across many different native languages, whether a learner's first language has a definite article at all is one of the strongest predictors of whether they will accidentally drop "the" or "a" in English.9
Having articles in one's first language helps somewhat, but does not fully solve the problem, because languages divide up meanings like genericity (talking about a whole category, e.g. "the dinosaur is extinct") differently, so Spanish, Turkish, and Japanese learners each show a different, language-specific pattern of mistakes.3,8,10
In plain terms
Beyond the meaning problem, articles are short, typically unstressed words, and learners \-- even those who have reached a very advanced, stable ('end-state') level \-- still omit or mis-time them in fast speech, partly because of how they fit into the rhythm and stress pattern of a sentence.6,15
In plain terms
Example
Some advanced non-native speakers supply grammatical markers like past tense or plural more reliably in speech than they supply articles, showing articles are especially vulnerable to being dropped compared to other grammar pieces.6
Even Arabic-speaking learners, whose native language does mark definiteness, make frequent errors adding "the" where it doesn't belong or leaving it out where it's required, because English's rules for when to use "the" are full of idiosyncratic exceptions (no article before general nouns like "shopping").13
In advanced learners' academic writing, article mistakes are one of the recurring error types that seem to "stick" permanently despite years of classroom instruction, a pattern researchers link to limited noticing of the error and insufficient corrective feedback rather than lack of exposure alone.16
Learners' article choices are also affected by whether a noun is a new topic, a continuing topic, or a reintroduced one in a conversation or story, and how strongly the learner's first language marks these distinctions affects their English article accuracy.12
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