The IPA symbol /θ/ appears in the pronunciation of thread /θrɛd/. Which sound does /θ/ represent?
/θ/ — the voiceless "th" sound:
/θ/ is the IPA symbol for the voiceless dental fricative — the "th" in "think", "thread", "through", "three".
How to produce /θ/: Place the tip of your tongue between your upper and lower teeth (or just behind your upper teeth), then blow air through. Your vocal cords do NOT vibrate.
Tech words with /θ/:
thread /θrɛd/ — "thredd"
threshold /ˈθrɛʃhoʊld/
throughput /ˈθruːpʊt/
throttle /ˈθrɒtəl/
Common confusion with /ð/: /ð/ is the VOICED "th" — as in "this", "that", "the". The difference: /θ/ is whispered-th, /ð/ is voiced-th.
Non-native speakers often substitute /t/ or /s/ for /θ/ (producing "tread" or "sread" instead of "thread"). The tip-between-teeth position is the key physical cue.
2 / 5
A dictionary shows the pronunciation of cache as /kæʃ/. Which part of this IPA string tells you the vowel sound?
/æ/ — the "trap" vowel:
In /kæʃ/, the vowel is /æ/ — known as the "trap" vowel in British phonology. It sounds like the "a" in "cat", "batch", "back", "stack".
IPA breakdown of /kæʃ/:
/k/ — the "k" sound (voiceless velar stop)
/æ/ — the "trap" vowel — short, open, front vowel — your mouth opens wide
/ʃ/ — the "sh" sound (voiceless palato-alveolar fricative)
The /æ/ vowel in tech words:
cache /kæʃ/ — "kash"
batch /bætʃ/ — "batch"
stack /stæk/ — "stack"
Lambda /ˈlæmdə/ — "LAM-duh"
backend /ˈbækɛnd/ — "BAK-end"
Contrast with /ɑː/ (the "palm" vowel): /kɑːʃ/ would sound like "KAHSH" — this is NOT cache. The /æ/ is shorter and more forward in the mouth.
3 / 5
The IPA shows asynchronous as /eɪˈsɪŋkrənəs/. What does the ˈ (vertical mark) before "sɪŋ" tell you?
ˈ (primary stress mark) in IPA:
In IPA, ˈ placed before a syllable means that syllable carries the primary (main) stress — it is pronounced louder, longer, and at a higher pitch than other syllables.
Breaking down /eɪˈsɪŋkrənəs/:
/eɪ/ — "ay" — unstressed first syllable (the "a-" prefix)
/ˈsɪŋ/ — "sing" — primary stress here (loudest)
/krə/ — "kruh" — unstressed
/nəs/ — "nus" — unstressed
Result: "ay-SING-kruh-nus" — 4 syllables, stress on second.
Secondary stress (ˌ): A lower mark ˌ indicates secondary stress — weaker than primary but stronger than unstressed. Example: infrastructure /ˌɪnfrəˈstrʌktʃər/ — secondary on "in-", primary on "STRUK".
Why stress matters: In English, wrong stress makes words nearly unrecognisable — "ay-sin-KRON-us" (wrong stress) sounds very different from "ay-SING-kro-nus".
4 / 5
Which IPA symbol correctly represents the vowel in kernel /ˈkɜːrnəl/?
/ɜː/ — the "nurse" vowel in "kernel":
The first syllable of "kernel" /ˈkɜːrnəl/ uses /ɜː/ — a long, mid-central vowel often called the "nurse" vowel (from the keyword "nurse"). It sounds like the vowel in "bird", "word", "heard", "learn".
How to produce /ɜː/: Your tongue is in the centre of your mouth, neither front nor back, neither high nor low. The sound is "ur" — but without the American retroflex r for British speakers.
Tech words with /ɜː/:
kernel /ˈkɜːrnəl/ — "KUR-nel"
merge /mɜːrdʒ/ — "murj"
server /ˈsɜːrvər/ — "SUR-ver"
worker /ˈwɜːrkər/ — "WUR-ker"
network /ˈnɛtwɜːrk/ — "NET-wurk"
The schwa /ə/: The second syllable of "kernel" uses /ə/ — the unstressed neutral vowel ("nel" → /nəl/). Schwa is the most common vowel in English — it appears in ALL unstressed syllables in natural speech.
5 / 5
The IPA for throughput is /ˈθruːpʊt/. What does the ː (colon-like mark) after /uː/ indicate?
/ː/ — the length mark in IPA:
The triangular colon /ː/ in IPA indicates that the preceding vowel is long — roughly twice the duration of a short vowel. It does NOT mean a pause.
/uː/ vs /ʊ/ in throughput /ˈθruːpʊt/:
First syllable: /uː/ — LONG "oo" — like "boot", "through" → "throo"
Second syllable: /ʊ/ — SHORT "oo" — like "book", "put" → "put"
The full word: "THROO-put" — first syllable long, second syllable short.
IPA vowel length contrasts in tech vocabulary:
heap /hiːp/ — long /iː/ (like "hee-p")
bit /bɪt/ — short /ɪ/ (like "bit")
cache /kæʃ/ — short /æ/
parse /pɑːrs/ — long /ɑː/
throughput /ˈθruːpʊt/ — long /uː/ then short /ʊ/
Why it matters: English uses vowel length to distinguish words — "ship" /ʃɪp/ vs "sheep" /ʃiːp/, "hit" /hɪt/ vs "heat" /hiːt/.