changes needed for vertical writing. Tonal marks As shown in the following table, tone marks for the second, third, and fourth tones are shared between bopomofo and pinyin. In bopomofo, the mark for first tone is usually omitted but can be included, while a dot above indicates the fifth tone (also known as the neutral tone). In pinyin, a macron (overbar) indicates the first tone, and the lack of a marker usually indicates the fifth (light) tone. Unlike Hanyu Pinyin, Bopomofo aligns well with the Chinese characters in books whose texts are printed vertically, making Bopomofo better suited for annotating the pronunciation of vertically oriented Chinese text. When used in conjunction with Chinese characters, Bopomofo is typically placed to the right of the Chinese character vertically in both vertical print and horizontal print or to the top of the Chinese character in a horizontal print (see Ruby characters). Example Below is an example for the word "bottle" (): Erhua transcription Words rhotacized as a result of erhua are spelled with attached to the syllable (like ). In case the syllable uses other tones than the 1st tone, the tone mark is attached to the penultimate letter standing for syllable nucleus, but not to (e.g. ; ; ). Comparison Pinyin Bopomofo and pinyin are based on the same Mandarin pronunciations; hence there is a one-to-one correspondence between the two systems: 1 Not written. 2 is written as after , , , or . 3 / is written as / after /, /, /, /. 4 is pronounced (written as ) when it follows an initial. Chart Use outside Standard Mandarin Bopomofo symbols for non-Mandarin Chinese varieties are added to Unicode in the Bopomofo Extended block. Taiwanese Hokkien In Taiwan, Bopomofo is used to teach Taiwanese Hokkien, and is also used to transcribe it phonetically in contexts such as on storefront signs, karaoke lyrics, and film subtitles. Three letters no longer used for Mandarin are carried over from the 1913 standard: 23 more letters were added specifically for Taiwanese Hokkien: Two tone marks were added for the additional tones: ˪, ˫ Cantonese The following letters are used in Cantonese. If a syllable ends with a consonant other than -an or -aan, the consonant's letter is added, then followed by a final middle dot. -ㄞ is used for [aːi] (aai) (e.g. 敗, ㄅㄞ baai6) -ㄣ is used for [ɐn] (an) (e.g. 跟, ㄍㄣ