Why Is My Child So Hard to Understand? Speech Clarity in Bilingual Children

Quick answer: should I be worried if my child is difficult to understand?

Some unclear speech is expected while young children are learning to talk. What matters is your child’s age, how much people understand, the kinds of mistakes they make, whether their speech is becoming clearer, and what happens across both languages. Bilingualism does not cause a speech disorder,[1] but bilingual children can have speech difficulties just like any other child.

What to look at

• Who understands your child: you, other relatives, teachers, or people who don’t know them?
• Are they unclear in one language or in both?
• Is their speech gradually getting clearer?
• Do they get frustrated, give up, or avoid talking?
• Are particular sounds hard, or are whole words unrecognisable?

Read this article in Arabic

What does “speech clarity” actually mean?

Therapists call this intelligibility: how much of what your child says another person can actually understand.

It helps to separate four things that all have to go right:

• Knowing what they want to say
• Putting the words and the sentence together
• Pronouncing those words clearly
• Speaking at a volume, pace and rhythm that others can follow

A child can have plenty of words and good sentences and still be hard to understand. That often points to speech sounds rather than to how much language the child has.

How clear should my child’s speech be at their age?

You may have seen a rule saying children are 50% understandable at two, 75% at three and 100% at four. More recent research suggests that this rule is too rigid.

A study of 538 typically developing children found considerable variation in how quickly speech became understandable to unfamiliar adults. For multiword speech, children across the middle-to-lower part of the typical range reached 50% intelligibility between 34 and 46 months, 75% between 46 and 61 months and 90% between 62 and 87 months. The authors concluded that children should be at least 50% intelligible by 48 months and that, for children in the middle and lower range, clarity can continue developing through approximately nine years of age.[2]

This study involved children whose primary home language was American English. Its figures should not be treated as Arabic-English bilingual norms or as pass-or-fail milestones. They are useful for showing how variable intelligibility can be and why being 100% intelligible by four is not a reliable universal rule. Intelligibility also changes with sentence length, the listener’s familiarity and how much context the listener has.

An earlier study by the same research group likewise found that only a small number of children approached 100% intelligibility by 47 months.[3]

Treat the right-hand column as reasons to ask someone, not as a threshold your child has failed.

Why can I understand my child when other people can’t?

Because you have information nobody else has. You know their word for the toy. You know the routine they’re describing. You recognise “tar” as car because you’ve heard it four hundred times. You read the gesture, the pointing and the situation, and your brain fills in the sounds that weren’t actually there.

That doesn’t mean other people aren’t trying, and it doesn’t by itself mean something is wrong. But the gap between you and an unfamiliar listener is genuinely useful information. In the research above, clarity was measured by adults who had never met the child, which is a much stricter test than family conversation.[2] If your child’s nursery keyworker or a grandparent who visits monthly understands noticeably less than you do, that gap is worth mentioning.

Why might my child’s speech be unclear?

They are still learning speech sounds

Some sounds arrive early and some arrive late, and which ones are late depends on the language.

They simplify words in predictable ways

Most young children do this. You may recognise:

• Dropping the ends of words
• Replacing back sounds like k with front ones like t, so “car” becomes “tar”
• Squashing consonant clusters, so “spoon” becomes “poon”
• Using one sound in place of several different ones

Cluster reduction is a common developmental pattern in English, but it doesn’t carry the same meaning in every language. In one study of Jordanian Arabic-speaking children aged three to six and a half, cluster reduction did not meet the researchers’ threshold for a commonly occurring pattern in any age group.[4] Other work involving younger Jordanian children has observed cluster reduction before age three,[12] so this should not be taken to mean it never occurs in typical early development.

They find one particular sound difficult

A single tricky sound, like a lisp on s, is a different situation from a child whose whole speech system is hard to follow.

Their speech falls apart in longer sentences

Longer utterances need more planning and coordination. Parents often say “I understand single words, but not when he tells me a story.” That pattern is worth reporting, because it’s easy to miss in a short appointment.

They speak very fast, very quietly, or with an unusual rhythm

Pronunciation isn’t the only thing that affects clarity.

Hearing may be involved

Repeated ear infections and fluctuating hearing can affect how a child hears and produces sounds.[5] If there’s any doubt about hearing, ask your GP or health visitor about a hearing test.[10]

There may be a speech sound disorder

This is considered when a child’s speech is much harder to understand than other children of the same age speaking the same language. It’s not rare: around 12 children in every 100 have a speech sound disorder, and about half of those also have language difficulties.[5] An assessment is what identifies the nature of the difficulty. It is not a label waiting to be applied.

Is my child unclear because they speak two languages?

No. Hearing or using two languages does not cause a speech sound disorder,[1] and unclear speech is not a reason to stop using your home language.

What two languages do change is what you should expect to hear.

• Each language has its own set of sounds and its own rules about how they combine.
• A sound may exist in one language and not the other. Arabic has pharyngeal and emphatic consonants that English does not have. English /p/ and /v/ are not native phonemes in many Arabic varieties. English /θ/ and /ð/, the sounds commonly written as th, exist in Modern Standard Arabic and in some spoken dialects, but are replaced by other sounds in many others.
• Your child may have far more practice speaking one language than the other.
• One language can influence the other. This can produce an accent or a predictable difference, not a disorder.
• The same underlying difficulty can look different in each language, because each language gives it different things to trip over.
• Mixing languages in a sentence is normal bilingual development and says nothing about pronunciation.[6]

RCSLT guidance explains that children growing up with two or more languages generally develop speech sounds across their languages at about the same time, but exposure matters: the language they hear most may develop earlier.[5]

What if my child is unclear in only one language?

This is the situation most articles skip, and it doesn’t have a single answer. One-language difficulty does not automatically mean “nothing is wrong”, and it does not automatically mean “there is a disorder”. It depends on:

• How long your child has heard and used that language
• Which language they use most, and with whom
• Whether the difficult sounds exist in their other language
• Whether their pronunciation is expected for their family’s accent or dialect
• How they compare with children who have similar language experience, rather than with monolingual children
• Whether there are subtler signs in the other language once someone looks properly

The principle that matters: a speech disorder should not be diagnosed from English performance alone when English is not your child’s only language. Assessment should gather information about all the languages and dialects your child uses, and difficulties do not always look identical across languages.[7]

RCSLT advises against referring a child solely because their English sounds different when speech in the home language is developing as expected. However, it also recommends referral when speech development in any language seems slow, unusually different or concerning.[5] The important point is that English should never be considered in isolation.

Difference, accent or speech disorder: how can I tell?

An Arabic and English example. A five-year-old Arabic-dominant child might say “bark” for park because /p/ is not a native phoneme in many Arabic varieties. They might also say “tree” for three, but whether this reflects cross-linguistic influence depends on their dialect: /θ/ occurs in Modern Standard Arabic and some spoken dialects but is replaced by /t/ or /s/ in others.

Now imagine that the same child says [ʔ] for ق in Arabic, so قال sounds like “ʔaal”. In urban Ammani speech that is simply how ق is commonly pronounced. In a family from a rural or Bedouin background, the expected pronunciation might be different. The child hasn’t changed; the yardstick has.

This is why Arabic norms matter, and why English ones don’t transfer.

What Jordanian research tells us

Amayreh and Dyson tested 180 children in Jordan aged two to six years four months and classified Arabic consonants as early, intermediate or late.[8] Several emphatic and interdental consonants were classified as late when judged against the study’s Arabic targets. However, some of these targets have different accepted forms in colloquial speech. An apparent substitution may therefore reflect dialect rather than immaturity.

A more recent study of Ammani-Jordanian preschoolers found /χ/, /ħ/, /ʕ/ and /ʔ/ acquired before six, while /ʁ/ (غ) and /h/ had not yet reached the study’s acquisition criterion by six.[9] The studies do not agree fully on every sound, partly because age groups, elicitation tasks, dialects and definitions of “acquired” differ.

The practical message is not that parents need to memorise a consonant chart. It is that Arabic acquisition research is less extensive and particularly sensitive to dialect, task and the definition of “acquired”. English norms also vary by population and method, so no sound-age list should be applied without context.

Is this a speech problem or a language delay?

Parents use “speech delay” for both, and they’re different.

• Speech is how clearly sounds and words come out.
• Language is understanding words and sentences, and using them to say what you mean.

A child may have difficulty with one, with both, or with neither. And mixing languages is not evidence of confusion or a language disorder.[6]

If your worry is that your child isn’t saying much at all, rather than that what they say is hard to follow, the companion article is “My bilingual child isn’t talking yet. When should I worry?”

Signs that it may be time to seek advice

• Close family often can’t understand your child.
• Unfamiliar people understand very little, for your child’s age.
• Their speech isn’t getting clearer over time.
• They leave out many sounds or whole syllables.
• They use a very small range of consonants.
• The same word comes out differently each time they say it.
• Longer sentences become very hard to follow.
• They seem to struggle physically to organise speech.
• They get upset, withdraw, or avoid talking.
• Their speech is affecting school, friendships or confidence.
• You have concerns about hearing, about understanding, or about development more broadly.
• Something just doesn’t feel right to you.

Guidance from Berkshire Healthcare NHS Foundation Trust suggests speaking to a health visitor or GP if by around three to three and a half years a child has a limited vocabulary, poor understanding, or speech that is unintelligible most of the time.[10]

What should a bilingual speech assessment include?

Ask for an assessment that covers:

• Every language and relevant dialect your child uses
• Language exposure and use over time, not just today
• How your child communicates at home and at school
• Your observations and the teachers’ observations
• Speech samples, not one English test on its own
• Sounds and word patterns in each language
• Hearing history
• Whether errors reflect one language influencing the other
• How understandable your child is to familiar and unfamiliar listeners

The therapist does not have to speak Arabic fluently. Published guidance sets out how a clinician who doesn’t share a child’s languages can still assess properly: working with trained interpreters or bilingual colleagues, taking a full language history, using recordings and informal tasks where standardised tests don’t exist, and involving parents directly, including comparing the child’s productions with a parent’s own.[11]

What can I do at home?

Repeat the word correctly, without asking them to say it again

Child: “I want the tup.”

You: “You want the cup. Here’s your cup.”

Respond to the message, then model the word. Berkshire Healthcare’s guidance is explicit that you should respond to what the child says rather than to how clearly they said it, and that you shouldn’t make the child repeat words, because drawing attention to mistakes undermines confidence.[10]

Show that you’re listening

Get the message first. Correction can wait, and mostly isn’t needed.

Use gestures, choices and visual clues

Especially when frustration is building.

Ask for clarification gently

• “Can you show me?”
• “Did you mean the car or the star?”
• “I got the first bit. Tell me again?”

Don’t pretend you understood

Berkshire Healthcare’s guidance says this directly. Ask, or ask them to show you, and be reassuring when you truly can’t work it out.[10]

Keep speaking the languages you know best

Don’t switch the household to English or drop Arabic because speech is unclear. There is no evidence that helps, and good evidence that bilingualism isn’t the cause.[1][5]

Don’t turn every conversation into practice

Repeated drilling of hard words, exaggerating mistakes, or generic “mouth exercises” without professional guidance are not the answer.

Will my child grow out of it?

Some developmental speech errors do resolve. The difficulty is that age alone is not a reliable guide, and the research shows how much typical children vary from one another.[2] What matters more is the type of errors, how understandable your child actually is, whether clarity is improving, and whether communication is being affected.

Asking for an assessment doesn’t mean your child will need therapy. Often it means you get a clearer picture and stop wondering.

What happens if my child does need speech therapy?

Therapy is built around your child’s own sound system. It might target individual sounds, patterns that affect several sounds at once, or the planning behind speech. Goals should be about being understood in real life, not about performing sounds in a room. For a bilingual child, therapy should take account of how progress in one language may support the other. And you should come away with practical things to do, not an instruction to abandon your home language.

Final takeaway

Being hard to understand doesn’t mean your child is lazy, confused, or unable to communicate. It may reflect typical development, differences between their two languages, or a speech difficulty that would respond well to support. The useful next step is to look at the whole child across all their languages, rather than at English on its own.

Frequently asked questions

Why is my child talking but difficult to understand?

Talking a lot and being understood are different skills. Your child may have plenty of words and good sentences while still finding certain sounds hard, or losing clarity in longer utterances. That usually points to speech sounds rather than to language. If unfamiliar people understand noticeably less than you do, it’s worth an assessment.

At what age should a child’s speech be clear?

There is no single age. In one American-English study, unfamiliar adults’ understanding of multiword speech reached 50%, 75% and 90% between 34–46, 46–61 and 62–87 months respectively across the middle-to-lower part of the typical range.[2] These figures are guides, not universal milestones for bilingual children, and the old rule that every child should be 100% clear by four is too rigid.

Should strangers understand my two-year-old?

Not fully. At two, familiar adults understand considerably more than strangers do, and that gap is expected. What’s worth checking is whether even close family understand very little, or whether your child uses only a small handful of different consonants. Both are reasons to ask for advice rather than wait.

Should I be able to understand my three-year-old?

You will usually understand more than someone who does not know your child, but you may not understand every word. At three, mistakes are still expected. Seek advice if even familiar adults frequently cannot understand your child, their speech is not becoming clearer or communication is causing frustration.

Why can only I understand my child?

You know their vocabulary, their routines, their gestures and what they’re likely to be talking about, so your brain fills in the missing sounds. That’s normal and not a failing on anyone’s part. But a large gap between you and other listeners is genuinely useful information, and it’s worth mentioning to a therapist.

Is it normal for a four-year-old to have unclear speech?

Some unclear speech at four is common, and being 100% intelligible by four is not a reliable universal rule.[2] By this age, though, speech should be becoming much easier for people outside the family to follow. If others regularly need you to translate, that is a good reason to seek advice.

Does speaking two languages make a child’s speech less clear?

No. Bilingualism does not cause a speech sound disorder.[1] Children generally develop speech sounds across their languages at about the same time, although the language they hear and use most may develop earlier.[5] What two languages change is what you should expect to hear, because each language has its own sounds and the languages can influence each other.

What if my child is clear in Arabic but not in English?

Look at exposure first. If English arrived later or is used less, a developing English sound system is expected. Check whether the difficult English sounds exist in Arabic at all: /p/ and /v/ are not native phonemes in many Arabic varieties. If Arabic is developing as expected that is reassuring, but it is still worth asking if you remain concerned.

What if my child is clear in English but not in Arabic?

The same logic applies in reverse, with dialect added. A pronunciation that looks wrong against Modern Standard Arabic may be exactly right for how your family speaks, and Arabic acquisition research is particularly sensitive to dialect and to how “acquired” is defined.[8][9] A therapist needs to know which dialect your child hears at home.

Should we stop speaking our home language?

No. Bilingualism does not cause or contribute to speech, language or communication disorders.[1][5] There is no reason to stop using your home language because of a speech difficulty. Switching to a language you speak less comfortably can reduce the richness and ease of family conversation. Keep using the languages in which you can connect naturally with your child.

Will my child grow out of their speech difficulties?

Some children do, but age alone is not a reliable guide: intelligibility varies a great deal even among typically developing children.[2] Better indicators are whether clarity is improving over months, how unusual the errors are, and whether communication is being affected. If you are concerned, getting advice is more useful than relying on age alone.

How can I help without constantly correcting them?

Respond to what your child means, then say the word correctly yourself. “I want the tup” gets “You want the cup. Here’s your cup.” Guidance from Berkshire Healthcare NHS Foundation Trust advises responding to the message rather than the pronunciation, and not asking the child to repeat words, since that draws attention to the mistake.[10]

Does unclear speech mean my child has apraxia?

Not by itself. Most children with unclear speech do not have childhood apraxia of speech (CAS). CAS is rare, with an estimated prevalence of around one child in 1,000.[13] Even among children referred to speech and language therapy with a primary speech sound disorder, RCSLT reports that between 0.2% and 2.4% have CAS; most have a phonological delay or disorder.[13] Diagnosis depends on a combination of features rather than on low intelligibility or inconsistent words alone.[13]

When should I contact a speech and language therapist?

When unfamiliar people understand little for your child’s age, when clarity isn’t improving, when errors are unusual or inconsistent, when longer sentences fall apart, when your child is frustrated or avoiding talking, or when school or friendships are affected. You don’t need to meet a threshold. Being worried is reason enough.

Does my child need a hearing test?

If there is any doubt, yes. Children can have periods of reduced hearing from colds, ear infections or glue ear, which affects how they hear and produce sounds.[5] Ask your GP or health visitor, and go to every hearing test offered.

Where to go next

• Speech, language and feeding milestones: birth to 5 years — A way to explore what children typically do at each age. It describes age-related milestones and isn’t an assessment of how clearly your child speaks.
• Does My Child Need Speech Therapy? — What to notice, when to ask, and what happens next.

References

1. Royal College of Speech and Language Therapists. Bilingualism. https://www.rcslt.org/speech-and-language-therapy/clinical-information/bilingualism/
2. Hustad, K. C., Mahr, T. J., Natzke, P., & Rathouz, P. J. (2021). Speech development between 30 and 119 months in typical children I: Intelligibility growth curves for single-word and multiword productions. Journal of Speech, Language, and Hearing Research, 64(10), 3707–3719. https://doi.org/10.1044/2021_JSLHR-21-00142
3. Hustad, K. C., Mahr, T., Natzke, P. E. M., & Rathouz, P. J. (2020). Development of speech intelligibility between 30 and 47 months in typically developing children: A cross-sectional study of growth. Journal of Speech, Language, and Hearing Research, 63(6), 1675–1687. https://doi.org/10.1044/2020_JSLHR-20-00008
4. Marie, B. S., Qanawati, L. K., Zabalawi, D. A., Ali, A. M., & Najem, F. J. (2024). Development of phonological error patterns in Arabic-speaking children in Jordan. Communication Disorders Quarterly, 46(3), 135–145. https://doi.org/10.1177/15257401241246207
5. Royal College of Speech and Language Therapists. Speech sound disorders. https://www.rcslt.org/speech-and-language-therapy/clinical-information/speech-sound-disorders/
6. Byers-Heinlein, K., & Lew-Williams, C. (2013). Bilingualism in the early years: What the science says. LEARNing Landscapes, 7(1), 95–112. https://www.learninglandscapes.ca/index.php/learnland/article/view/Bilingualism-in-the-Early-Years-What-the-Science-Says
7. American Speech-Language-Hearing Association. Multilingual service delivery in audiology and speech-language pathology (Practice Portal). https://www.asha.org/practice-portal/professional-issues/multilingual-service-delivery/
8. Amayreh, M. M., & Dyson, A. T. (1998). The acquisition of Arabic consonants. Journal of Speech, Language, and Hearing Research, 41(3), 642–653. https://doi.org/10.1044/jslhr.4103.642
9. Mashaqba, B., & Hadban, F. (2024). Acquisition of gutturals by Ammani-Jordanian Arabic-speaking preschoolers. Journal of Speech, Language, and Hearing Research, 67(7), 2222–2243. https://doi.org/10.1044/2024_JSLHR-23-00085
10. Berkshire Healthcare NHS Foundation Trust. Helping children with unclear speech. https://www.berkshirehealthcare.nhs.uk/advice/communication-and-hearing/helping-children-with-unclear-speech
11. McLeod, S., Verdon, S., & the International Expert Panel on Multilingual Children’s Speech (2017). Tutorial: Speech assessment for multilingual children who do not speak the same language(s) as the speech-language pathologist. American Journal of Speech-Language Pathology, 26(3), 691–708. https://doi.org/10.1044/2017_AJSLP-15-0161
12. Mashaqba, B., Al-Shdifat, K., Al Huneety, A., & Abu Alhala, M. (2019). Acquisition of syllable structure in Jordanian Arabic. Communication Sciences & Disorders, 24(4), 953–967. https://doi.org/10.12963/csd.19657
13. Royal College of Speech and Language Therapists. (2024). Position paper on childhood apraxia of speech (CAS). https://www.rcslt.org/wp-content/uploads/2024/02/RCSLT-Childhood-Apraxia-of-Speech-CAS-Position-Paper-2024.pdf