Todo

Written units

ID	Variants				Ligated Variants
	isol	init	medi	fina	init	medi	fina
A	 a	 a e i o u oe ue hh	 a e i o u oe ue n ng hh	 a n		
Aa				 a			
B		 b jy	 b jy		 	 
B2				 b
Ch		 z	 z	 z
Cp		 j	 j	 j
Dp		 d	 d	 d
E			 e	 e			
G		 g	 ng g		 	 
G2				 ng
Gp		 gh	 gh		 	 
Hb		 g	 g
Hp			 g	 g
Hr			 hh lh	 hh
Hx			 h
Hx2		 h
I		 y	 i y			
I3				 i			
Ip			 i			
J		 c	 c	 c
Jb		 ch	 ch	 ch
K		 h	 h	 h	 	 
Kp		 kh	 kh	 kh	 	 
L		 l lh	 l lh	 l		
Lv			 lvs	 lvs
M		 m	 m			
M2				 m
N		 n	 n
N2		 n
Ny		 ny	 ny
O			 u ue	 ue			
Ob			 o	 o			
Op			 u	 u			
Ot			 oe	 oe			
Pp		 p	 p	 p	 	 
R		 r	 r	 r
S		 s	 s	 s
Sh		 sh	 sh	 sh
Tp		 t	 t	 t
U				 u ue
Up				 u
W		 f	 f	 f
Wb		 w	 w	 w
Yp			 jy
Zz		 zr	 zr	 zr
Zz2		 zr	 zr	 zr

Written form Wb. Written form Wb (used in Todo letter w) is similar to the written form D (used in Hudum letter d), but since the form Wb comes from the bent W and thus from beth, and the form D from lamedh, the two are represented differently.

Phonetic letters

The variants in gray indicate the fabricated variants, i.e. variants borrowed from other joining positions. The variants in yellow indicate the variants that are unattested in the modern orthography of Traditional Mongolian.

Letter	FVS	Variants
		isol	init	medi	fina
1820 ᠠ a	-			 A
	1	 A		 A A	 Aa
	2		 A A		 A
	3	 A A
1844 ᡄ e	-	 A E	 A E	 E	 E
	1			 A E
1845 ᡅ i	-	 A I3	 A Ip		 I3
	1		 A I	 A Ip
	2			 Ip
	3			 I
1846 ᡆ o	-	 A Ob	 A Ob	 Ob	 Ob
	1			 A Ob
1847 ᡇ u	-	 A Up	 A Op
	1	 A Op		 A Op	 U
	2			 O	 Op
	3			 Op	 Up
1848 ᡈ oe	-	 A Ot	 A Ot	 Ot	 Ot
	2			 A Ot
1849 ᡉ ue	-	 A U	 A O	 O
	1	 A O		 A O	 O
	2				 U
1843 ᡃ lvs	-	 → medi	 → medi	 Lv	 Lv
1828 ᠨ n	-	 → init	 N
	1			 N
	2	 → init 2	 N2	 A	 A
184A ᡊ ng	-	 → medi	 → medi	 A G	 A G2
184B ᡋ b	-	 → init	 B	 B	 B2
184C ᡌ p	-	 → init	 Pp	 Pp	 Pp
184D ᡍ h	-	 → init 2			 K
	1	 → init 1	 K	 K
	2		 Hx2	 Hx
184E ᡎ g	-	 → init 2			 Hp
	1	 → init 1	 G	 Hp
	2		 Hb	 G
	3			 Hb
184F ᡏ m	-	 → init	 M	 M	 M2
182F ᠯ l	-	 → init	 L	 L	 L
1830 ᠰ s	-	 → init	 S	 S	 S
1831 ᠱ sh	-	 → init 2			 Sh
	2		 Sh	 Sh
1850 ᡐ t	-	 → init	 Tp	 Tp	 Tp
1851 ᡑ d	-	 → init	 Dp	 Dp	 Dp
1852 ᡒ ch	-	 → init	 Jb	 Jb	 Jb
1853 ᡓ j	-	 → init	 Cp	 Cp	 Cp
1834 ᠴ z	-	 → init	 Ch	 Ch	 Ch
1854 ᡔ c	-	 → init	 J	 J	 J
1855 ᡕ y	-	 → init	 I	 I	 → medi
1837 ᠷ r	-	 → init	 R	 R	 R
1856 ᡖ w	-	 → init	 Wb	 Wb	 Wb
1838 ᠸ f	-	 → init	 W	 W	 W
1857 ᡗ kh	-	 → init	 Kp	 Kp	 Kp
1858 ᡘ gh	-	 → init	 Gp	 Gp	 → medi
1859 ᡙ hh	-	 → init	 A Hr	 A Hr	 A Hr
185A ᡚ jy	-	 → init	 B Yp	 B Yp	 → medi
185B ᡛ ny	-	 → init	 Ny	 Ny	 → medi
185C ᡜ zr	-	 → init	 Zz	 Zz	 Zz
	1	 → init 1	 Zz2	 Zz2	 Zz2
1840 ᡀ lh	-	 → init	 L Hr	 L Hr	 → medi

Final I3 in letter y, medial O and final U in letter w. Final I3 in letter y, medial O and final U in letter w are introduced in GB/T 36649—2018, where the written form I3 of letter y and the written form O of letter w in the examples tuwlay, and the written form U of letter w in the example daruw are all differences derived from letter analysis. Since tuulai and daruu are preferred, the written forms are marked in gray.

Initial AI and medial I in letter i, medial O and final O in letter oe, written form Y in letter y. These written forms are introduced in GB/T 36649—2018, showing the cognition between Todo e and Hudum ee, Todo i and Hudum i, Todo oe and Hudum oe, Todo y and Hudum y. Since cognition is not considered a basis for establishing a written form system, the letters in the running text are not analyzed for these forms with cognition associations, and therefore these written forms are marked in gray.

Initial N in letter n. A written unit is used for particle –ni in Todo, and is regarded as a stylistic variant of the written unit N, thus is not triggered by FVS.

Letter ny. The letter ny is introduced in 蒙汉词典 (增订本), but is not found in Todo literature. The appearance is subsequently succeeded by GB/T 36649—2018. The character is used by Hudum Ali Gali and Todo Ali Gali.

Shaping process

Letter classes

Class	Letters
masculine vowel	a, o, u
feminine vowel	e, oe, ue
neuter vowel	i
vowel	a, e, i, o, u, oe, ue, lvs
long vowel	a, e, o, oe
consonant	n, ng, b, p, h, g, m, l, s, sh, t, d, ch, j, z, c, y, r, w, f, kh, gh, hh, jy, ny, zr, lh
bowed written unit	B, Pp, G, K, Gp, Kp

Mongolian-specific phase

Shaping step	Letters	Condition	Mapping type
2. Syllabic	n	if precedes a vowel or a long vowel:	onset
		else if precedes a consonant:	devsger
	h, g	if precedes a masculine vowel or a masculine long vowel:	masculine_onset
		else if precedes a feminine vowel or a neuter vowel or a feminine long vowel:	feminine
		else if g follows a vowel or a long vowel:	masculine_devsger
3. Particle	n	if is in the specific particle dictionary that follows an MVS:	particle
4. Devsger	i	if follows a vowel or a long vowel:	vowel_devsger
	u	if follows u:	vowel_devsger
5. Post-bowed	a, i, u, ue	if follows a bowed written unit:	post_bowed

Conditional mapping

Letter	Mapping type	Variants
		isol	init	medi	fina
1820 ᠠ a	default				
	post_bowed				
1844 ᡄ e	default				
1845 ᡅ i	default				
	vowel_devsger			
1846 ᡆ o	default				
1847 ᡇ u	default				
	devsger			
	vowel_devsger				
	post_bowed				
1848 ᡈ oe	default				
1849 ᡉ ue	default				
	post_bowed				
1843 ᡃ lvs	default				
1828 ᠨ n	default				
	onset			
	devsger			
184A ᡊ ng	default				
184B ᡋ b	default				
184C ᡌ p	default				
184D ᡍ h	default				
	masculine_onset			
	feminine			
184E ᡎ g	default				
	devsger			
	masculine_onset			
	feminine			
184F ᡏ m	default				
182F ᠯ l	default				
1830 ᠰ s	default				
1831 ᠱ sh	default				
1850 ᡐ t	default				
1851 ᡑ d	default				
1852 ᡒ ch	default				
1853 ᡓ j	default				
1834 ᠴ z	default				
1854 ᡔ c	default				
1855 ᡕ y	default				
1837 ᠷ r	default				
1856 ᡖ w	default				
1838 ᠸ f	default				
1857 ᡗ kh	default				
1858 ᡘ gh	default				
1859 ᡙ hh	default				
185A ᡚ jy	default				
185B ᡛ ny	default				
185C ᡜ zr	default				
1840 ᡀ lh	default				

Function of the sign ƚ. The sign ƚ behaves as a base character in some cases, but its logic in the shaping process behaves as a combining mark. For this reason, the necessary preprocessing and postprocessing should be introduced: before the Mongolian-specific steps begin, ƚ is shaped in mark class, modifying the joining type of the characters before and after ƚ; after the Mongolian-specific steps finish, those signs ƚ that need to be represented as marks are shaped to ligature with the neighboring letters. These extra steps are not included in the condition table shown above, but are completed in the specific implementation.

References

• Information technology — Todo nominal characters, presentation characters and use rules of controlling characters. China national standard, GB/T 36649—2018.

• Liang Jinbao. (2021). The Transferring rules of Todo nominal form to variant form. Research on Mongolian Encodings, version 0.1.0 (April 18, 2020).

• Quejingzhabu. (2013). “Encoding of Todo”, in: 确精扎布蒙古文信息处理专辑. Hohhot: Inner Mongolian Education Press, pp. 295–309.

• Quejingzhabu, Geriletu. (1998). 卫拉特方言词汇. Hohhot: Inner Mongolia University Press.

• Eerdeni, Gerilema. (1988). 蒙古语常用词汇. Urumqi: Xinjiang People’s Press.

• Wuenqi, Airencai. (2005). 四体卫拉特方言鉴. Urumqi: Xinjiang People’s Press.

• Saierge. (2016). Research on the Todo script and its development of history. Doctoral dissertation, Inner Mongolia University.

• Mingzai. (2018). Тод бичгийн баримжаа кодын тухай санууламж. L2/19-136.

• Mongolian Language Institute (Inner Mongolian University). (1999). 蒙汉词典 (增订本). Hohhot: Inner Mongolia University Press.