Common mistakes by native language
Japanese speakers
Mistake: Pronouncing "of" with its full dictionary vowel [ɑv] and inserting a tiny pause before "all", producing "first — ov — all" as three separate chunks.
Why: Japanese phonology favors clear, evenly-timed mora, so learners often give every English word equal weight and a full vowel, resisting the reduction that native speech applies to function words like "of".
Fix: Treat "of" as a bridge, not a word: it shrinks to [əv] and its [v] immediately links onto the vowel of "all", giving [ˈfɝsəˈvɑl]. Practice saying "first-uh-vall" as one breath group before slowing back down to normal speed.
Korean speakers
Mistake: Devoicing the final [v] of "of" into something closer to [f], and adding a glottal stop between "of" and "all" to keep the words distinct.
Why: Korean does not have a phoneme like English [v], and syllable-final obstruents in Korean are typically unreleased, which encourages a clipped, disconnected transition instead of a smooth link.
Fix: Keep your bottom lip touching your top teeth and let voicing continue through the [v] as it flows into "all" — there should be no gap. The whole sequence "of all" becomes a single smooth syllable-like unit [əˈvɑl].
Chinese speakers
Mistake: Reading "first" with a released, aspirated final [t] before pausing, then starting "of all" as a fresh breath group.
Why: Mandarin syllables are closed and self-contained with clear final stops, so learners often insert a boundary at every English word edge rather than letting consonants and vowels flow across word boundaries.
Fix: Let the [st] cluster in "first" stay tight and unreleased, then move directly into the reduced "of" [əv] with no stop in between. Think of "first of all" as one rhythmic phrase, not three separate words: [ˈfɝsəˈvɑl].
Notes
"First of all" is one of the most common discourse markers in spoken English, used to signal the start of a list, an argument, or a response. Its pronunciation hinges on two connected-speech features: the reduction of "of" to a weak [əv], and the linking of that [v] straight into the vowel of "all", producing [ˈfɝsəˈvɑl]. Learners who pronounce "of" with its full, stressed vowel sound noticeably foreign and stilted, even though the grammar is perfectly correct — connected speech carries as much information about fluency as vocabulary does. Because this phrase almost always appears at A1 level in textbook dialogues yet is rarely drilled for pronunciation, it is an ideal early target: mastering the of-reduction here builds a template learners can reuse in dozens of other "of"-phrases, from "a lot of" to "kind of" to "most of them".