Africa	Eurasia	Papunesia	Australia	North America	South America
75	108	72	37	57	54
18%	26%	17%	9%	14%	13%

 

Number of PNG combinations
	No agreement	2-3	4	5	6	7 or more	Total
NSLs	73	5	9	20	84	171	362
Partial NSLs	5	2	0	1	2	2	12
Non-NSLs	19	4	2	2	1	1	29
Total	97	11	11	23	87	174	403

Table 2. Number of NSLs, partial NSLs, and non-NSLs

 

Number of PNG combinations
	No agreement	2-3	4	5	6	7 or more	Total
Africa	3	0	1	3	15	34	56
Eurasia	34	2	1	5	26	27	95
Papunesia	17	1	3	3	10	33	67
Australia	11	1	1	0	2	22	37
North America	3	0	1	5	19	28	56
South America	5	1	2	4	12	27	51
Total	73	5	9	20	84	171	362

Table 3. Number of NSLs, broken up by area

 

Table 4. Number of families with NSLs, broken up by area

 

Creissels (2005:50) warns that the morphemes termed “subject pronouns” in descriptions of African languages are mostly not really separate words and should be reanalyzed as dependent forms. Following this, African non-NSLs without subject agreement on the verb would actually be NSLs with subject agreement on the verb. Nonetheless, languages with seven or more PNG combinations would still remain, among languages with subject agreement on the verb, the most widespread geographically and genealogically. There are 13 African languages among the 19 non-NSLs without subject agreement on the verb. Among these African languages, the “subject pronouns” distinguish seven or more PNG combinations in six languages, six combinations in six languages, and five combinations in one language. In this case, in Africa there would be in total four NSLs with five PNG combinations, 21 NSLs with six combinations, and 40 NSLs with seven or more combinations. Moreover, the number of families would be two for NSLs with five combinations, ten for NSLs with six combinations, and 17 for NSLs with seven or more combinations.

 

3.2 Results in detail

 

This subsection aims at explaining in more detail the quantitative results in the previous subsection. I will first present the languages without subject agreement on the verb and continue, in increasing order of PNG combinations, to languages that have seven or more combinations.

 

The majority (13 languages) of the 19 non-NSLs without subject agreement are African languages. Among these, the majority (9 languages) are Atlantic-Congo languages. In Eurasia, there are four non-NSLs without subject agreement on the verb: Ingush, a Nakh-Daghestanian language from the Caucasus (Nichols 2011), Swedish, Norwegian, and Danish. In Papunesia, there are two non-NSLs without subject agreement on the verb: Abun, a language isolate of Indonesia (Berry and Berry 1999), and Amis, an Austronesian language spoken in Taiwan (Wu 2006, Chen 2008). Among the five partial NSLs without subject agreement on the verb, there are three African languages of the Atlantic-Congo family: Noon (Soukka 2000), Dii (Bohnhoff 2010), and Yoruba (Timothy Adeyemi Akanbi, personal communication). These three languages allow null subjects only in the third person. The other two partial NSLs without subject agreement on the verb are: Zuni, a language isolate of the USA (Nichols 1997, Newman 1965) that allows null subjects only in the third person, and Yawanawá, a Pano-Tacanan language of Brazil (Paula 2004) that allows only third-person singular null subjects.

 

The three African NSLs without subject agreement on the verb are Ts’ixa (Fehn 2014) and Khwe (Kilian-Hatz 2008), two Khoe-Kwadi languages of Botsawana, and Xun, a Kxa language spoken in Namibia (Heine and König 2015). Among the 34 Eurasian NSLs without subject agreement on the verb, the majority (26 languages) are spoken in East or Southeast Asia. The other cases are found in the Indian subcontinent (seven languages) and in the Caucasus, where the Nakh-Daghestanian language Lezgian (Haspelmath 1993) is spoken. Moreover, there is a considerable number (14 languages) of Sino-Tibetan languages among these Eurasian NSLs. Among the 17 NSLs of Papunesia without subject agreement on the verb, the majority (10 languages) are Austronesian languages. The 11 NSLs without subject agreement on the verb of Australia are all Pama-Nyungan languages, except the Tangkic language Kayardild (Evans 1995). The three NSLs without subject agreement on the verb of North America are all spoken in the USA: the Yuki-Wappo language Wappo (Thompson et al. 2006), the Uto-Aztecan language Northern Paiute (Thornes 2003), and the Yokutsan language Yowlumne (Weigel 2005). The NSLs without subject agreement on the verb of South America are Epena Pedee, a Chocoan language of Colombia (Harms 1994), Sanuma, a Yanomamic language of Brazil (Borgman 1990), Iskonawa, a Pano-Tacanan language of Peru (Zariquiey 2015), Hup, a Nadahup language of Brazil (Epps 2008), and Qawasqar, a Kawesqar language of Chile (Aguilera 2001, Clairis 1985).

 

The non-NSLs with two to three PNG combinations are Mbodomo, an Atlantic-Congo language spoken in Cameroon, Koiari, a Koiarian language spoken in Papua New Guinea,  Dutch, and English. Mbodomo marks, in the simple past and past perfect, first and second person as high tone on the verb, while the third person is marked as low tone on the verb. There is no number distinction (Boyd 1997:95). Koiari marks, in the perfect conjugation, the first- and third-person singular with the suffix -nu and all the remaining person and number combinations with -nua. The imperfect conjugation makes the same paradigmatic distinctions (Dutton 1996:23). Dutch present tense suffixes mark the first-person singular with zero, the second- and third-person singular with -t and the three persons in the plural with -en (De Schutter 1994:455-456).

 

The partial NSLs with two to three combinations are Trumai, a language isolate spoken in Brazil, and Igbo, an Atlantic-Congo language spoken in Nigeria. Trumai allows only third- person null subjects (Raquel Guirardello, personal communication) and marks the third-person with the enclitics -n/-e, while the other person and number combinations are unmarked. Number is expressed by independent words: wan (plural) and a (dual). (Guirardello 1999:55, 95). In Igbo, null subjects are allowed only in the second- and third-person singular (Ogbonna Anyanwu, personal communication). The second-person singular is marked with the clitic i- and the third-person singular with the clitic o-; the other person and number combinations are unmarked (Anyanwu 2012:377).

 

The NSLs with two to three PNG combinations are the following. Siona, a Tucanoan language spoken in Ecuador, marks the third-person singular feminine of the present tense with the suffix -ko, third-person singular masculine with -hi, and the other combinations by -jɨ (Bruil 2014:178). Bunan, a Sino-Tibetan language spoken in India, makes a distinction between first-person and non-first person agreement in the past and future tenses. In the past tense, first person singular is marked with -kidza, first person-plural with -kits^ha, and the other combinations are unmarked (Widmer 2014:562). In the future tense, non-first person singular is marked with -kaniː, non-first-person plural by -k^hak, and the first-person is unmarked (Widmer 2014:569). Jarawa, a Jarawa-Onge language spoken in the Andaman Islands, distinguishes the three persons, but there is no number distinction. First person is marked with the prefix m-, second person with ŋ-, and third person with h- (Kumar 2012:81). Thao, an Austronesian language spoken in Taiwan, marks the first-person singular actor with the suffix -k, the second person-singular with -nu, and the other combinations are unmarked. The nominative clitics also have the same PNG distinctions (Wang 2004:189). Ngarla, a Pama-Nyungan language spoken in Australia, marks the third-person dual with -pula, the third-person plural with -ya, and the other combinations are unmarked (Westerlund 2015:64).

 

The non-NSL in the database with four PNG combinations are Anejom, an Austronesian language of Vanuatu, and German. In the nineteenth century, the subject/tense markers of Anejom had a rich agreement system including a dual/trial distinction in the three persons and clusivity. Lynch (2000:92-95) shows that this system is undergoing considerable impoverishment and hypothesizes that the language is developing a four-way paradigm in the aorist: first person-singular is marked with ek, second-person singular with na, third-person singular with et, and all persons in the plural by era. As shown by the present tense conjugation of the verb legen ‘lay’ in (5), German has syncretism between the third-person singular and second-person plural, as well as between the first- and third-person plural. The past suffixes have a slightly different paradigmatic distinction, but the number of PNG combinations is the same. The sample in this study contains no partial NSL with four combinations.

 

(5)	German				(6)	Aghu (van den Heuvel 2016:37)
		sg	pl			1sg	dade
	1	lege	legen			n1sg	dā
	2	legest	leget			1pl	dadoã
	3	leget	legen			n1pl	dakenã

 

The NSLs with four combinations are the following. Aghu, a Nuclear Trans New Guinea language spoken in Indonesia, makes a distinction between first person and non-first person, both in the singular and plural, as shown by the conjugation of the verb da(k) ‘hear’ in (6). Awa Pit, a Barbacoan language spoken in Colombia (Curnow 1997:181-186, 190), and Wambon (de Vries and de Vries-Wiersma 1992:23) make the same paradigmatic distinctions as Aghu. Nez Perce, a Sahaptian language spoken in the USA, marks the third person with hi-, while the first and second person are marked with zero. Singular and plural number are distinguished by suffixes (Rude 1985:33-35). Canela-Krahô, a Nuclear-Macro-Je language spoken in Brazil, marks the first-person exclusive with the prefix i-, the first-person inclusive with pa-, the second-person with a-, and the third-person with ih-. These prefixes are pluralized by the independent form me (Popjes and Popjes 1986:175). The non-past endings of Darma, a Sino-Tibetan language spoken in India, have syncretism between the second-person singular and first-person plural, and there is no number distinction in the third person, as shown in (7). The subject suffixes of Kunuz Nubian, a Nubian language spoken in Sudan, have syncretism between the second- and third-person singular, as well as between the first- and second-person plural, as shown in (8). The subject agreement markers of Kokota, an Austronesian language spoken in the Solomon Islands, mark the first-person exclusive with a, the first-person inclusive with da, the second person with o, and the third person with e. There is no number distinction (Palmer 2009:173). The subject clitics of Nhanda, a Pama-Nyungan language spoken in Australia, distinguish the first-person singular with -wa, the second person singular with -wana, the first-person plural with -nyja, and the other PNG combinations are unmarked (Blevins 2001:84).

 

(7)	Darma (Willis 2007:353)					(8)	Kunuz Nubian (Abdel-Hafiz 1988:148)
		sg		pl				sg	pl
	1	-di		-dɛn			1	-i	-u
	2	-dɛn		-dɛni			2	-Ø	-u
	3		-da				3	-Ø	-a

 

The two non-NSLs with five combinations are Icelandic and French. Icelandic is exemplified in (9) by the conjugation of the verb telja ‘believe’. In this case, there is syncretism between the second- and third-person singular. The preterite tense of French has the same paradigmatic distinctions (Batchelor and Chebli-Saadi 2011:247). The only partial NSL with five combinations is Irish, which allows null subjects only in non-syncretic verb forms (Mac Congáil 2004:117). The past habitual tense of Irish has syncretism between the third-person singular and second-person plural, as illustrated in (10) by the conjugation of the verb cuir ‘put’.

 

(9)	Icelandic (Thráinsson 1994:159)				(10)	Irish (Mac Congáil 2004:128)
	sg	pl					sg	pl
	1	tel	teljum			1	chuirinn	chuirimis
	2	telur	teljið			2	chuiteá	chuireadh
	3	telur	telja			3	chuireadh	chuiridís

 

Among the 20 NSLs with five PNG combinations, the most frequent pattern (seen in 11 languages) distinguishes the singular and plural in the first and second person, without number distinction in the third person. This pattern is illustrated in (11) by the subject affixes of Choctaw, a Muskogean language of the USA. The only non-NSL with six combinations is Wutung, a Sko language of Papua New Guinea, which is exemplified in (12) by the conjugation of the verb ha ‘go’. There is syncretism between the first-person singular and second-person plural, and no syncretism between the other PNG combinations.

 

(11)	Choctaw (Broadwell 2006:137)					(12)	Wutung (Marmion 2010:300)
		sg	pl				1sg	ha
	1	-li	il-				2sg	hma
	2	ish-	hash-				3sg.m	qa
	3	Ø					3sg.f	hwang
							1pl	hna
							2pl	ha
							3pl	hnya

 

The partial NSLs with six combinations are Kenga, a Central-Sudanic language spoken in Chad, and Finnish. Kenga is exemplified in (13) by the conjugation of the verb àkā ‘see’ in the aorist. This conjugation has no number distinction in the third person, while the other person and number combinations do not display any syncretism. Finnish (Karlsson 1999:61) distinguishes the same PNG combinations as Spanish in (1), that is, the three persons in the singular and plural. Both Kenga (Vandame 1968:35) and Finnish (Karlsson 1999:62) allow null subjects in the first and second, but not in the third person. Among the 84 NSLs in the sample with six PNG combinations, the vast majority (65 languages) have the combinations shown by Spanish in (1).

 

(13)	Kenga (Vandame 1968:35)
	1sg	m-ákà
	2sg	ákà
	3sg	àkā
	1pl.excl	j-àkā
	1pl.incl	j-àk-kī
	2pl	ák-kī
	3pl	àkā

 

Evenki, a Tungusic language spoken in Russia, is the only non-NSLs in the sample with seven or more PNG combinations. Evenki elaborates the Spanish-type pattern with the addition of an inclusive/exclusive contrast, as seen in (14) by the present conjugation of the verb baka- ‘find’. The partial NSLs with seven or more combinations are Mekens, a Tupian language spoken in Brazil, and Modern Hebrew. In Mekens, intransitive subjects can be omitted, while transitive subjects can be omitted only in the third-person singular (Galucio 2001:78, 80). Mekens makes the same person and number distinctions as Evenki in example (14). According to Glinert (1989:53), Modern Hebrew allows null subjects in the past and future tenses, but in the present tense null subjects are allowed only in the third person. The past tense conjugation of the verb saper ‘tell’ in (15) elaborates the Spanish-type pattern with the addition of masculine/feminine gender in the second- and third-person singular and in the second-person plural.

 

(14)	Evenki (Nedjalkov 1997:259)			(15)	Modern Hebrew (Berman 1997:318)
	1sg	bakad'am			1sg	sipárti
	2sg	bakad'anni			2sg.m	sipárta
	3sg	bakad'aran			2sg.f	sipárt
	1pl.excl	bakad'arav			3 sg.m	siper
	1pl.incl	bakad'arap			3 sg.f	sipra
	2pl	bakad'aras			1 pl	sipárnu
	3pl	bakad'ara			2 pl.m	sipartem
					2 pl.f	siparten
					3 pl	sipru

 

Unlike among the NSLs with five and six PNG combinations, there is no specific pattern that is considerably frequent among the 171 NSLs with seven or more combinations. The most frequent pattern (seen in 25 languages) has the same seven distinctions as the Evenki example in (14).

 

4. Conclusion

 

In this paper, I examined the correlation between agreement richness and the occurrence of null subjects based on a sample of 403 languages. Agreement richness was measured according to the number of PNG combinations encoded by subject agreement on the verb. It was found that, among languages with subject agreement on the verb, NSLs with seven or more combinations are the most widespread geographically and genealogically. NSLs without subject agreement on the verb are more widespread than NSLs with seven or more combinations only in Eurasia. The findings confirm the generally assumed view that languages with rich subject agreement on the verb tend to allow null subjects, since such languages are well spread geographically and genealogically.

 

A possible explanation for this tendency is economy, which is a propensity to economize time and effort in the expression and interpretation of constructions. The relationship between null subjects and agreement richness investigated here is an example of the principle of economy working on language: in order to prevent the use of an overt subject or the reliance on contextual information, languages tend to encode clear information on the PNG of the subject through subject agreement on the verb.

 

However, languages are not always economical. As seen previously, Evenki has unambiguous information on the person and number of the subject and nevertheless requires overt subjects. Moreover, rich agreement systems might become poorer sometimes (Siewierska 2004:277-281). In fact, when languages without subject agreement on the verb are considered, NSLs with seven or more combinations are not the most geographically and genealogically widespread, as the results showed. Therefore, another explanation that must be taken into account is the specific histories of each family.

 

Since this is a large-scale cross-linguistic study, some distinctions could not be easily made. For example, there might be more partial NSLs than it were found, as the authors of reference grammars sometimes do not pay due attention to null subject phenomena. Another distinction that could not be addressed here is that some NSLs are more likely to omit the subject than others (Cole 2010, Posio 2012). Future research might deal with these distinctions among genealogically and areally diverse languages.

 

Appendix

 

The following is a list of the 403 languages in the sample. The languages are divided into the six areas proposed by Hammarström and Donohue (2014) and the families according to Hammarström et al. (2018) are given in parentheses.

 

AFRICA: Amharic, Egyptian Arabic, Tamazight, Tamashek, Hausa, Somali, Oromo, Lele, Iraqw, Coptic (Afro-Asiatic); Godié, Kisi, Wolof, Dii, Yoruba, Eleme, Oko, Kar, Fyem, Zulu, Cicipu, Igbo, Kujireray, Temne, Degema, Oshindonga, Mbodomo, Mbalanhu, Koromfe, Chichewa, Babungo, Balanta, Gbaya, Ewe, Dagaare, Noon, Northern Sotho, Shona, Sango, Lucazi, Eton, Swahili, Nzadi, Gola (Atlantic-Congo); Dholuo, Lango, Turkana, Anywa (Nilotic); Chabu, Kunama, Laal, Sandawe, Siamou (Isolates); Lumun (Narrow Talodi); Deiga (Kadugli-Krongo); Fur (Furan); Haro (Ta-Ne-Omotic); Hoa, Xun (Kxa); Ik (Kuliak); Jamsay (Dogon); Kabba, Kenga, Mbay (Central Sudanic); Kanuri (Saharan); Koyra Chiini, Tadaksahak (Songhay); Maba (Maban); Mano, Zialo (Mande); Murle (Surmic); Ts'ixa, Khwe (Khoe-Kwadi); Kunuz Nubian (Nubian); Tira (Heibanic).

EURASIA: Abkhaz, Kabardian (Abkhaz-Adyge); Kham, Sunwar, Bunan, Ersu, Mishmi, Burmese, Hkongso, Dhimal, Darma, Tangam, Mandarin, Meithei, Dzongkha, Lepcha, Tujia, Eastern Kayah Li, Rabha, Tibetan, Bai (Sino-Tibetan); Ainu (Ainu); Albanian, German, Bulgarian, Pashto, Spanish, Icelandic, French, Persian, Latin, Punjabi, Czech, Russian, Polish, Lithuanian, Irish, Sinhala, Latvian, Urdu, Hindi, Armenian, Marathi, Dutch, Romanian, Sanskrit, Kashmiri, Italian, Portuguese, Modern Greek, Danish, Norwegian, Swedish, English (Indo-European); Modern Hebrew, Gulf Arabic (Afro-Asiatic); Basque, Burushaski, Kusunda, Nihali, Nivkh (Isolates); Gadaba, Malayalam, Brahui, Tamil, Telugu, Kannada (Dravidian); Buriat, Mangghuer, Mongolian (Mongolic); Chukchi, Itelmen (Chukotko-Kamchatkan); Hungarian, Estonian, Tundra Nenets, Finnish, Pite Saami (Uralic); Manchu, Evenki, Udihe (Tungusic); Georgian, Svan (Kartvelian); Great Andamanese (Great Andamanese); Ingush, Lezgian (Nakh-Daghestanian); Jarawa (Jarawa-Onge); Western Yugur, Turkmen, Uzbek, Kirghiz, Kazakh, Turkish, Turfan Uyghur (Turkic); Ket (Yeniseian); Mundari, Pnar, Semelai, Vietnamese, Chrau, Korku, Khmer (Austroasiatic); Japanese (Japonic); Korean (Koreanic); Zoulei, Lao, Thai (Tai-Kadai); Xong (Hmong-Mien); Kolyma Yukaghir (Yukaghir).

AUSTRALIA: Duuŋidjawu, Nhanda, Ngarla, Kalkatungu, Yanyuwa, Dyirbal, Kuuk Thaayorre, Diyari, Kuku Yalanji, Yidiɲ, Bāgandji, Wargamay, Wangurri, Warrongo, Wangkajunga, Martuthunira, Wirangu (Pama-Nyungan); Bininj Gun-Wok, Enindhilyakwa (Gunwinyguan); Bunuba (Bunaban); Emmi (Western Daly); Gaagudju, Tiwi, Wagiman (Isolates); Kayardild, Yukulta (Tangkic); Limilngan (Limilngan-Wulna); MalakMalak (Northern Daly); Mangarayi (Mangarrayi-Maran); Mawng (Iwaidjan Proper); Nakkara (Maningrida); Ngan'gityemerri (Southern Daly); Nyulnyul, Yawuru (Nyulnyulan); Wambaya (Mirndi); Wardaman (Yangmanic); Worrorra (Worrorran).

PAPUNESIA: Abau, Mehek (Sepik); Abun, Bilua, Duna, Lavukaleve, Maybrat (Isolates); Dom, Tauya, Yagaria, Aghu, Korafe, Usan, Ma Manda, Kewapi, Fore, Lower Grand Valley Dani, Una, Mauwake, Wambon (Nuclear Trans New Guinea); Amanab, Imonda (Border); Amis, Fehan Tetun, Indonesian, Maori, Kokota, Lha'alua, Anejom, Gayo, Cebuano, Yapese, Rukai, Puyuma, Paiwan, Buru, Tondano, Rapanui, Kwamera, Tukang Besi, Tinrin, Thao, Woleaian, Chamorro, Big Nambas, Madurese, Ida'an, Atayal, Amis, Javanese, Samoan, Hawaiian, Niuean, Mualang, Ilocano (Austronesian); Olo, Au, Yeri (Nuclear Torricelli); Barupu, Wutung (Sko); Bauzi (Geelvink Bay); Daga (Dagan); Iatmul, Manambu (Ndu); Kapau (Angan); Koiari (Koiarian); Komnzo (Morehead-Wasur); Kunimaipa (Goilalan); Teiwa, Makalero (Timor-Alor-Pantar); Motuna (South Bougainville); Ternate (North Halmahera); Yimas (Lower Sepik-Ramu).

NORTH AMERICA: Laguna Keres (Keresan); Slave, Navaho, San Carlos Apache, Tlingit (Athabaskan-Eyak-Tlingit); Arapaho, Plains Cree, Nishnaabemwin, Yurok (Algic); Assiniboine, Lakhota, Biloxi, Tutelo (Siouan); Cherokee, Seneca, Oneida (Iroquoian); Chimariko, Euchee, Kutenai, Molalla, Seri, Washo, Zuni (Isolates); Choctaw (Muskogean); Chol, Huastec, Itzaj Maya (Mayan); Lowland Chontal (Tequistlatecan); Ineseño Chumash (Chumashan); Cupeño, Warihio, Northern Paiute, Classical Nahuatl, Southeastern Tepehuan, Pipil (Uto-Aztecan); West Greenlandic, Central Alaskan Yupik (Eskimo-Aleut); Guazacapán (Xincan); Hualapai, Maricopa (Cochimi-Yuman); San Francisco del Mar Huave (Huavean); Huehuetla Tepehua (Totonacan); Kiowa (Kiowa-Tanoan); Maidu (Maiduan); Chalcatongo Mixtec, Otomí (Otomanguean); Yakima, Nez Perce (Sahaptian); Nuuchahnulth (Wakashan); Nxa'amxcin (Salishan); Teribe, Pech (Chibchan); Southern Pomo (Pomoan); Sierra Popoluca (Mixe-Zoque); Wappo (Yuki-Wappo); Wichita (Caddoan); Yowlumne (Yokutsan).

SOUTH AMERICA: Apalai, Wai Wai, Kuikuro, Tiriyó (Cariban); Ashéninka Perené, Paresi-Haliti, Warekena, Tariana (Arawakan); Awa Pit (Barbacoan); Muylaq' Aymara (Aymaran); Betoi, Guató, Iatê, Kanoê, Kwaza, Movima, Muniche, Mỹky, Páez, Trumai, Puinave, Yurakaré, Urarina (Isolates); Karajá, Canela-Krahô, Maxakalí (Nuclear-Macro-Je); Iskonawa, Yawanawá, Cavineña (Pano-Tacanan); Cubeo, Ecuadorian Siona (Tucanoan); Epena Pedee (Chocoan); Hup (Nadahup); Ika (Chibchan); Kamaiurá, Mundurukú, Tapiete, Mekens, Urubu-Kapoor (Tupian); Kulina (Arawan); Mako (Jodi-Saliban); Mamaindê (Nambiquaran); Mapuche (Araucanian); Ocaina (Huitotoan); Pilagá (Guaicuruan); Qawasqar (Kawesqar); Huallaga Quechua, Imbabura Quechua (Quechuan); Sanapaná (Lengua-Mascoy); Sanuma (Yanomamic); Tehuelche (Chonan); Wampis (Chicham); Wari (Chapacuran); Wichí (Matacoan).

 

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