1. Interlanguage developed as a concept in Error Analysis.
While Error Analysis has fallen out of favor, studies of Interlanguage have not. Why?
Because Interlanguage can be studied empirically.
Three areas of Interlanguage inquiry:
Systematicity / Variation
Development sequences
L1 influence 1

2. Interlanguage: Systematicity
Recall that an interlanguage is the “language system that the learner constructs out of the linguistic data to which [s/he] has been exposed” (LF&L, p. 60).
Many studies of consider the “system” of interlanguages. While interlanguage may be non-target-like, it may nevertheless be systematic – that is, rule-governed at any particular moment.
Many scholars investigate the systematicity that may underlie non-target-like interlanguages.
“May underlie”: other non-target-like features of interlanguage may be nonsystematic variation.

3. Interlanguage: Systematicity
Huebner, T. (1983). Linguistic systems and linguistic change in an interlanguage. Studies in Second Language Acquisition, 6(1), 33–53.
Case study of the English IL development of a Hmong man in Hawaii. 17 hours of recorded speech examined, with attention given to two structures, among them his use of “da,” something like the English definite article “the.”
“Yu tol da Jaepanii gow da cher.”
[“You told the Japanese woman that you were going to the church.”]
“Da” used in 64 percent of NP environments appropriate to the definite article.

4. Interlanguage: Systematicity
“Da” used in 64 percent of NP environments appropriate to the definite article.
But what is the “appropriate” NP environment for definite articles? What is the rule for the use of the definite (the) and indefinite article (a/n) in English?
Son 1: Dad gave me a car.
Son 2: Not the car? 
Son 1: No, a Taurus. or
Son 1: No, the Taurus.
What is Son 2 referring to? 
What difference does the pair of replies given by Son 1 indicate?

5. Interlanguage: Systematicity
What is the “appropriate” NP environment for definite articles?
Noun phrases may refer to something specific (specific referent, +SR) and / or to something known to the hearer (+HK) – or not (-SR; -HK).

6. Interlanguage: Systematicity
Quadrant 1: The lion is a noble animal (-SR, +HK).
Quadrant 4: Used in equative and other structures (-SR, -HK).
Quadrant 3: Dad gave me a Taurus (+SR, -HK). “A” refers to a specific Taurus, but not one known to the hearer.

7. Interlanguage: Systematicity
Quadrant 3: Dad gave me a Taurus (+SR, -HK). “A” refers to a specific Taurus, but not one known to the hearer.
Quad 2: Dad gave me the Taurus. (+SR, +HK) “The” refers to a specific Taurus known to the hearer.

8. Interlanguage: Systematicity
“Da” used in 64 percent of correct NP environments.
In most of the other 36 percent of NP environments that required the definite article, the NP was the topic of the sentence [“topic”: whatever the sentence is about. The tree is magnificent.]
Huebner theorized that his informant had developed an IL rule for the use of his definite article as follows: use “da” in NP environments characterized by +SR, +HK, -Topic.

9. Interlanguage: Systematicity
use “da” in NP environments characterized by +SR, +HK, -Topic.
Logic: If it is the topic of the sentence, it is known to the hearer by default, and therefore doesn’t need a definite article; perhaps this is a kind of simplification rule, to eliminate redundant features / structures. If the NP is not the topic, Huebner’s informant may have theorized, it does need the definite article.
Conclusion: IL systematic, if non-target-like.

10. IL: Development Sequences, First Lge Learning
First language development: Brown, Roger. (1973) A first language. Cambridge: Harvard Univ. Press.
HLAL, p. 3: Case study; 4 years (diachronic / longitudinal); 3 children from age 2; samples every 1-2 weeks. Acquisition of 14 morphemes:
1. -ing
3 on
3 in
plural “s”
past irregular
possessive “s”
uncontracted copula (I am)
articles “a” “the”
past regular
3rd person regular “s”
3rd person irregular “has”
uncontracted aux (he is eating)
contracted copula (I’m)
contracted aux (he’s coming)

11. IL: Development Sequences, First Lge Learning
0.86, 0.87, and 0.89 correlations among three children for order of acquisition of 14 morphemes.
de Villiers, J., & de Villiers, P. (1973). A cross- sectional study of the acquisition of grammatical morphemes. Journal of Psycholinguistic Research 2(3), 267–278.
Synchronic / cross sectional study; 21 children ages 16 – 40 months, two 1.5-hour sessions.
Three methods of analysis showed 0.78, 0.84, and correlations among children for order of acquisition of same 14 morphemes.

12. IL: Development Sequences, First Lge Learning
Structures most frequently produced in child’s environment not necessarily learned earlier.
Positive reinforcement had no impact on acquisition of morphemes.
What can we conclude, epistemologically, from these findings? I.e., what process explains first language acquisition?
Language learning is not a behavioral process of habit formation, but is driven by something else. 12

13. IL: Development Sequences, SLA
Very productive area of inquiry in SLA
Methodological variations:
Longitudinal / diachronic (like Brown): small number of subjects studied over a period of time; v. cross-sectional / synchronic (like de Villiers & de Villiers): large number of subjects at a specific time.
Demographic variations:
children v. adult SLA
Language variations:
Meisel, J.M., Clahsen, H., & Pienemann, J. (1981). On determining developmental stages in natural second language acquisition. SSLA, 3, 109–135.

14. IL: Development Sequences, SLA
Development stages variations (HLAL pp. 82–93):
Development sequences for
Interrogative formation
Negation formation
Relative clause formation
Morphemes (Dulay and Burt)
Pragmatics (Rose)

15. IL: Development Sequences, Dulay & Burt
Literature Review (pp. 37–38) – 2 pages!
Error analysis reveals “creative construction,” p. 37: “children gradually construct rules for speech they hear, guided by universal innate mechanisms which cause them to formulate certain types of hypotheses about the language system being acquired, until the mismatch between what they are exposed to and what they produce is resolved.”
The “second episode,” p What’s this?
Their study of English morpheme acquisition by three different groups of Spanish speakers.
What limits their conclusions, methodologically?
Results may be driven by common first language.

16. IL: Development Sequences, Dulay & Burt
Methods of Data Collection
longitudinal or cross-sectional?
who are subjects? how does this answer the constraint of “episode #2”?
how did the researchers find subjects?
how did they collect data?
what is the Bilingual Syntax Measure (BSM) (pp. 39–40)

17. IL: Development Sequences, Dulay & Burt
Methods of Data Collection
what morphemes (“functors”) did they study?

18. IL: Development Sequences, Dulay & Burt
Methods of Data Analysis
how was the data analyzed / coded?
obligatory occasions
0 points if no morpheme supplied in O.O.:
She is dance___
1 point if morpheme is supplied, but it is incorrect:
She is dances
2 points if correct morpheme is supplied:
She is dancing.

19. IL: Development Sequences, Dulay & Burt
Methods of Data Analysis
group individual scores morpheme X summed
total possible obligatory occasions

20. IL: Development Sequences, Dulay & Burt Results

21. IL: Development Sequences, Dulay & Burt
Results
What do the declining lines mean re: the acquisition of specific morphemes?
What do they mean relative to one another? – i.e. to the Spanish and Chinese language groups?
Note correlations, p. 50: / What do these mean?

22. IL: Development Sequences, Dulay & Burt Related Studies

23. IL: Development Sequences, Dulay & Burt Related Studies

24. IL: Development Sequences, Dulay & Burt Related Studies
What conclusions can we draw?

25. IL: Development Sequences, Dulay & Burt
Conclusion
Speakers of numerous native languages (Spanish, Cantonese, Greek, Persian, Italian, etc.), at various ages, acquire English morphemes in remarkably similar orders.
These studies “provide … a strong indication that universal cognitive mechanisms are the basis for the child’s organization of a target language, and that it is the L2 system, rather than the L1 system that guides the acquisition process” (p. 52).

26. IL: Development Sequences, Dulay & Burt
Critique
Meisel, Clahsen, & Pienemann (1981) challenge Dulay and Burt. By focusing exclusively on target language structures (she is dancing), D&B ignore systematic non-target-like grammars that may exist in informants’ interlanguages.

27. Interlanguage: First Language Influence
Markedness 
Phenomenon A in some language is more marked than phenomenon B if the presence of A implies the presence of B, but the presence of B does not imply the presence of A (implicational relations).
Marked or unmarked?
Sarah is a senior.
Sarah is a student.
If she is a senior, she must be a student, so this proposition is marked.
If she is a student, then she may be a senior, but we don’t know, so this proposition is unmarked.

28. Interlanguage: First Language Influence
Markedness 
Phenomenon A in some language is more marked than phenomenon B if the presence of A implies the presence of B, but the presence of B does not imply the presence of A (implicational relations).
Markedness Differential Hypothesis
Those areas of the target language which different from the native language and are more marked than the native language will be difficult.
Those areas of the target language which are different from the native language, but are not more marked than the native language, will not be difficult.

29. Interlanguage: First Language Influence
Markedness 
English and French both have the phoneme / ž /.
“pleasure” / “jamais”
In English words, / ž / never occurs syllable initial (distinguished from words borrowed from French, like “Jacques”).
BUT (markedness studies show), the syllable initial / ž / is not marked in English. Thus, while the phonology of French is different than English (relative to the distribution of the phoneme / ž /), that particular phonology will not be difficult for native English speakers to learn.

30. Interlanguage: First Language Influence
Markedness 
Eckman, F. (1977). Markedness and the contrastive analysis hypothesis. Language Learning, 27,