How to find syllable boundaries in Hanyu Pinyin

Syllable boundaries are extremely easy to locate when Mandarin Chinese is written in Hanyu Pinyin:

Hanyu Pinyin's syllables are presumed to begin with a consonant (including y and w, for the purpose of simplicity) or consonant cluster (ch, sh, or zh) unless something -- the beginning of a word, a hyphen, or an apostrophe -- indicates otherwise.

Although the rule above is enough all by itself, I'll add a bit more information to help make things clearer, if need be.

As written in Hanyu Pinyin:

Syllables always end with a vowel (a, e, i, o, u, ü) or [n]g, n, or r.
Every consonant other than h, g, n, and r can come only at the beginning of a syllable.
The only combinations of consonants that can appear at the beginning of a syllable are ch, sh, and zh.
The only combinations of consonants that can appear anywhere other than at the beginning of a syllable are ng, and, much less often, nr, and ngr.
Apostrophes come before any syllable that begins with a, e, or o, unless that syllable comes at the beginning of a word or immediately follows a hyphen or other dash. (Review the rules on apostrophes for more information.)
Apostrophes, hyphens, and other dashes come only at syllable breaks.

To review Mandarin's syllables, see combinations of initials and finals in Hanyu Pinyin.

Here are the rules for syllable boundaries in Hanyu Pinyin, as found in Chinese Romanization: Pronunciation and Orthography, by Yin Binyong.

When a single consonant (including w and y) appears in the middle of a polysyllabic word, it always marks the beginning of the next syllable. Thus:

běifāng (the North) is two syllables, běi-fāng

tāmen (they) is two syllables, tā-men

máoyī (sweater) is two syllables, máo-yī

dànàn (disaster) is two syllables, dà-nàn

When two or three consonants appear together in the middle of a polysyllabic word, the last one marks the beginning of the next syllable. Thus:

fěnbǐ (chalk) is two syllables, fěn-bǐ

mǎnyì (satisfied) is two syllables, mǎn-yì

lángān (railing) is two syllables, lán-gān

dòngwù (animal) is two syllables, dòng-wù

bàofēngyǔ is three syllables, bào-fēng-yǔ

These two rules apply to syllables that begin with a consonant, and to those that begin with the vowels i, u, and ü, since these in syllable-initial position are written yi, wu, and yu, and treated as consonants.

Actually, rule number 2 above isn't worded quite right, as these examples demonstrate:

bànchéng (complete) is bàn-chéng, not bànc-héng
zhēnshi (truly) is zhēn-shi, not zhēns-hi

Additionally, rule number 2 doesn't describe how to deal with four consonants in a row:

wǎngzhàn (website) is wǎng-zhàn, not wǎngz-hàn

And it doesn't tell what to do with the extremely rare cases of five consonants in a row:

tāngrshì (trifling/unimportant matters; sb. of scant means) is tāngr-shì
shuǐcōngrshìde (bright and beautiful -- of girls) is shuǐ-cōngr-shì-de

That's why I prefer to restate the rule as what I've written in the box near the top of this page.

All this is very easy -- certainly far easier than the syllable breaks in English or even Italian. The terrible, terrible practice of InTerCaPiTaLiZaTion of Mandarin words -- as seen on Taipei's street signs (NanJing, ChongQing, ZhongXiao, etc.) and, increasingly, elsewhere -- is thus all the more ridiculous. Hanyu Pinyin uses capital letters the same way English does: to mark the beginnings of sentences and to indicate proper nouns. Any capital letters within words only makes those words harder to read. Never write "PinYin" or any other such thing.

If you've read this page and reviewed the rules on apostrophes, you should be ready for the Pinyin syllable-break quiz.