A Vietnamese tone belongs phonologically to the whole syllable, but Quốc ngữ prints its mark on one selected vowel letter. Those are different facts: hearing the tone over hòa does not mean every vowel receives a grave mark. The spelling system selects one graphic host. Review the six marks themselves on Writing the Six Tones before working through the placement patterns here.
This guide consistently uses the centered convention common in contemporary digital text: hòa, khỏe, thúy, thủy. You will also encounter hoà, khoẻ, thuý, thuỷ in names, schoolbooks, overseas publications, and other editorial traditions. The competing forms are readable, and labels such as “old” and “new” are not used consistently across publishers; for work in this guide, use hòa, khỏe, thúy, thủy.
First find the actual vowel sequence
Before placing a tone, separate the onset from the rhyme. The u in qu and the i in gi participate in conventional onset spellings, so counting visible vowel letters without parsing can select the wrong host.
| Word | Onset for practical spelling | Vowel-bearing part | Tone host |
|---|---|---|---|
| quà | qu | a | à |
| quý | qu | y | ý |
| già | gi | a | à |
| gì | gi spelling with written i as host | i | ì |
Bạn mua quà gì cho bà?
What gift are you buying for Grandma?
Quý nhớ gọi cho mình nhé.
Quý, remember to call me, okay?
The personal name Quý is capitalized and keeps its acute on y. Never move or drop a tone merely because a keyboard makes another form easier to type.
The practical placement decision
Use this sequence:
- Remove a recognized onset such as qu, gi, ngh, or tr from consideration.
- Identify a final consonant: m, n, ng, nh, p, t, c, ch.
- Identify the vowel nucleus and any surrounding glides.
- If ê, ô, ơ, ư, ă, or â is the nucleus, keep the tone with that vowel-quality letter.
- Apply the established pattern for the remaining open or closed sequence.
Open versus consonant-closed sequences
An open sequence has no final consonant. A consonant-closed sequence is followed by a coda such as n, ng, t, or c. The contrast is especially clear in the alternating spellings ia/iê, ua/uô, ưa/ươ.
| Pattern | No final consonant | With final consonant | Placement insight |
|---|---|---|---|
| ia / iê | mía, phía | tiếng, hiền, Việt | open ia hosts the mark on i; closed iê hosts it on ê |
| ua / uô | múa, của | muốn, buồn, cuốn | open ua uses u; closed uô uses ô |
| ưa / ươ | cửa, lửa | đường, tưởng, nước | open ưa uses ư; closed ươ uses ơ |
| yê | khuya follows a related open spelling | Nguyễn, chuyện, tuyết | closed yê takes the mark on ê |
Phía trước có một cửa hàng bán mía.
Up ahead there's a shop selling sugarcane.
Mình muốn cuốn sách tiếng Việt này.
I want this Vietnamese-language book.
Nguyễn kể một chuyện vui trên đường về.
Nguyễn told a funny story on the way home.
The forms tiếng, muốn, đường, and Nguyễn have final consonants, so their centering patterns place the mark on ê, ô, ơ, ê respectively. Nghiêng has the same iê + ng structure as a closed sequence but carries ngang, so there is no visible mark.
Open sequences with a final glide
Written i/y and u/o often represent final glides after a main vowel. The tone remains with the main vowel rather than moving to the final glide:
| Rhyme | Examples | Host |
|---|---|---|
| ai / ay / ây | mái, tay, thấy | a or â, represented by the first letter |
| ao / au | áo, cháu, đau | the first written vowel |
| oi / ôi / ơi | hỏi, tối, mời | o, ô, or ơ |
| ui / ưi | túi, gửi | u or ư |
| eo | mèo, kẹo | e |
Bạn bỏ áo mới vào túi giúp mình.
Please put the new shirt in the bag for me.
Tối nay cháu mời bà ăn chè.
Tonight I'd like to invite you to have sweet soup, Grandma.
Calling all of these “two main vowels” hides the logic. The second letter often writes an offglide, while the mark identifies the nucleus that carries the rhyme's main vowel quality.
The house convention for oa, oe, and uy
The sequences oa, oe, uy show the most visible competition between publishing conventions. This guide uses:
| Guide form | Alternative encountered in print | Guide repair |
|---|---|---|
| hòa | hoà | hoà → hòa |
| khỏe | khoẻ | khoẻ → khỏe |
| thúy, thủy | thuý, thuỷ | thuỷ → thủy |
Dạo này sức khỏe của Thúy khá hơn rồi.
Thúy's health has improved lately.
Hai bên đã hòa giải sau cuộc họp.
The two sides reconciled after the meeting.
These differences normally do not change pronunciation or meaning. They are editorial variants, not permission to place marks randomly. Follow one style consistently, and preserve a person's officially written name or a quoted title even if it follows the other convention.
Vowel-quality marks stay attached
When the nucleus is written with ă, â, ê, ô, ơ, or ư, the tone combines with that letter: tuần, thuế, muốn, thuở, nước, gửi. Never detach the tone from the vowel-quality letter to create a sequence such as thúê.
Tuần sau mình phải đóng thuế.
Next week I have to pay tax.
Thuở nhỏ, bà sống ở một làng ven biển.
When she was young, Grandma lived in a coastal village.
Thuở is an important pattern: the horn identifies ơ as the nucleus, so the hỏi mark also appears there. The preceding u functions as a glide in the rhyme. The phrase thuở nhỏ is (somewhat literary/written); everyday speech also commonly uses hồi nhỏ.
A natural correction in context
— Bạn viết “sức khoẻ” à? Bài này dùng quy ước “sức khỏe” nhé. — Được rồi, mình sẽ sửa cả “hoà bình” thành “hòa bình” cho thống nhất.
— Did you write sức khoẻ? This article uses the sức khỏe convention. — All right, I'll also change hoà bình to hòa bình for consistency.
The conversation is about editorial consistency, not about pronunciation. Both spellings are readable, but a publication should state and enforce its style.
Unicode and normalization
A syllable with a stacked letter and tone, such as ệ or ỡ, can be encoded as a precomposed character or as multiple combining code points. Search and validation can fail even when the screen looks right. Use a Vietnamese input method and normalize stored text to NFC. Never move a mark by copying a freestanding accent character over a different vowel.
Common Mistakes
1. Following the alternative convention inside this guide
❌ Chúng tôi muốn sống trong hoà bình.
Non-house spelling here — hoà uses the alternative placement.
✅ Chúng tôi muốn sống trong hòa bình.
We want to live in peace.
The repair keeps the whole-syllable huyền tone but moves its graphic host to o, matching this guide's convention.
2. Counting u in qu as the nucleus
❌ qùa
Incorrect — the grave mark has been attached inside the qu onset spelling.
✅ quà
gift
Once qu is identified as the onset, a is the available tone host.
3. Marking the first letter of closed iê/uô/ươ
❌ tíêng, múôn, đừơng
Incorrect — these closed sequences have the wrong graphic host.
✅ tiếng, muốn, đường
language/voice; want; road
The final consonant co-occurs with iê, uô, ươ, and the mark belongs on ê, ô, ơ.
4. Moving a mark for visual convenience
❌ Nguyẽn đang học tiéng Việt.
Incorrect — both marks have been placed on nonstandard hosts.
✅ Nguyễn đang học tiếng Việt.
Nguyễn is studying Vietnamese.
5. Omitting the mark because placement feels uncertain
❌ Thuy nói mình vẫn khoe.
Incorrect — the missing marks turn names and words into incomplete or different forms.
✅ Thủy nói mình vẫn khỏe.
Thủy says she's still well.
Uncertainty is a reason to check a dictionary or input method, never a reason to publish unmarked text.
Key Takeaways
- Tone scopes over the syllable but is written on one selected vowel.
- Parse qu and gi before deciding which letters form the vowel sequence.
- Open ia/ua/ưa and closed iê/uô/ươ use different hosts.
- Final glides i/y/u/o do not usually take the mark away from the nucleus.
- This guide uses hòa, khỏe, thúy, thủy and labels hoà, khoẻ, thuý, thuỷ as an alternative editorial convention.
Now practice Vietnamese
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Start learning Vietnamese →Related Topics
- Writing the Six TonesA1 — Write each Vietnamese tone with its correct name and mark while keeping tone signs distinct from vowel-letter diacritics.
- Tone Marks with Diphthongs and TriphthongsA2 — Learn which vowel carries the Vietnamese tone mark in complex nuclei such as oa, uy, iê, uô, ươ, and uyê.
- Hỏi and Ngã: Pitch plus PhonationC1 — How hỏi and ngã contrast in Northern Vietnamese, merge in much southern speech, and remain distinct in standard spelling.
- Generic Người TaB2 — How người ta presents people in general, an unspecified human source, or a contextually understood person while managing distance and stance.