Why do 'strengths' and 'sixths' fall apart when I say them?

Because those specific words are close to the physical limit of what a single English syllable asks a mouth to do, and very few languages ask for anything near that many consonants in a row with no vowel to break them up.

30-second version: "Strengths" is /s t r ɛ ŋ k θ s/ — six consonants around one vowel, four of them stacked at the end with zero vowels between /ŋ/, /k/, /θ/ and /s/. Most of the world's languages max out at two or three consonants in a row; English regularly asks for four or five. The fix isn't saying it faster — it's building the cluster up one consonant at a time until the sequence is automatic.

Why these particular words are outliers

Most languages have limits on how many consonants can sit next to each other without a vowel breaking them up — linguists call this a syllable's phonotactics. Spanish, Japanese, and Mandarin all sit toward the restrictive end of that range. English sits toward the permissive end, and a handful of words push right up against the edge of what's physically sayable: strengths (/strɛŋkθs/), sixths (/sɪksθs/), twelfths (/twɛlfθs/), glimpsed (/glɪmpst/). Even fluent native speakers often simplify these in casual speech — dropping the /θ/ in sixths, for instance, is common and rarely noticed. That's worth knowing before you set yourself an unreasonable target: the goal is a clean, intelligible cluster, not museum-perfect articulation of every consonant every time.

That said, dropping consonants inconsistently, or dropping the wrong one, is a different problem from the native-speaker simplifications above — it's the pattern covered in why final consonants go missing, and it's worth ruling out first.

How sayit shows you where the cluster breaks

A six-consonant cluster gives an alignment six chances to go wrong, and sayit's per-word breakdown scores every one of them independently rather than judging the whole word as one pass/fail unit. On "strengths," you might see the initial /str/ onset land cleanly while the final /ŋkθs/ cluster shows a deletion at the /θ/ — that's a completely different fix from a substitution earlier in the word, and the breakdown names exactly which slot failed rather than leaving you to guess from a low overall score.

Building the cluster up, piece by piece

Trying to produce the whole cluster at full speed from the start is usually where this goes wrong. Build it instead:

1. 1.Say the vowel and the sounds immediately after it alone: "eng" (/ɛŋ/).
2. 2.Add one consonant: "engk" (/ɛŋk/).
3. 3.Add the next: "engkth" (/ɛŋkθ/).
4. 4.Add the last: "engkths" (/ɛŋkθs/).
5. 5.Attach the front of the word: "strengkths" → "strengths."

Each step should feel almost trivial before you add the next consonant. If a step feels hard, you added two sounds at once — go back one step.

Drill it

Record: "The strength of six-tenths and twelfths tested his strengths." It's deliberately dense — four of the hardest English clusters in one sentence — so treat it as a stress test, not a warm-up. If a lighter start is more useful, the Spanish-speaker consonant cluster guide has a gentler progression through onset clusters like street and spring before tackling word-final stacks.

How do I know it's improving?

Look for the deletion moving later in the cluster before it disappears entirely — a learner who drops two consonants in "sixths" and later drops only one is making real progress even though both takes might get the same check verdict. The number of phones matched, not just the final verdict, is the more honest week-to-week signal for a word this dense.

Try it

Open sayit free — no install, no card — and build "strengths" up through the five steps above, checking the breakdown after each one. Watching the target phone sequence fill in from the middle out is the fastest way to see the cluster actually forming.