It has been argued that the Mainland Scandinavian languages differ from English in that they permit filler-gap dependencies into adjunct clauses (Anward, 1982; Hagström, 1976), which are standardly treated as strong islands for extraction(Huang, 1982). A closer look suggests that extraction from adjunct clauses is also possible in English, provided that a coherence relation (e.g., a causal, as opposed to a purely temporal relation) holds between the events referred to by the matrix and the adjunct clause (Truswell, 2011). The same restriction appears to hold in Swedish. However, English contrasts with Swedish in that it has been argued to disallow extraction from finite adjuncts. Observations like these raise important questions regarding filler-gap association in island domains and cross-linguistic variation. First, if coherence matters for extraction from adjunct clauses, then adjuncts appear to contrast with other island domains, in which filler-gap association has been claimed to be suspended, such as in relative clause islands in English (e.g.,Traxler & Pickering, 1996). Second, if finiteness is a potential locus of variation, then this must be explained and related to other evidence of cross-linguistic and inter-individual variation (Kush et al., 2017; Phillips, 2013; Sprouse et al., 2016). 

We conducted two acceptability judgment experiments, one for English and one for Swedish, to investigate the hypothesis that semantic coherence facilitates extraction in both languages, whereas finiteness degrades extraction, but only in English. In our materials, we first manipulated the telicity of the matrix verb such that sentential coherence was either augmented(coherent, 1a and 2a) or impeded(non-coherent, 1band 2b), and then manipulated the finiteness of the adjunct clause ([finite/non-finite] in 1and 2). Long-distance dependencies were tested in the form of question formation in English (1) and topicalization in Swedish (2).

Forty sets of items were created and distributed across four presentation lists, interspersed with 80distractor sentences. Fifty-seven Swedish and 72 English mono-lingual, native speakers rated the sentences using a 7-point Likert scale(1 = “completely unacceptable” to 7 = “completely acceptable”), as presented using Google forms.The z-score adjusted responses for each condition in the two languages are presented in Figure1 and 2. Linear mixed models were used to analyze normalized z-score responses. As expected, coherence significantly improved extraction for both Swedish (β= 0.191, t = 4.792, p<.001) and English (β= 0.121, t = 3.853, p< .001). Furthermore, a significant finiteness by coherence interaction was found for English, in which finiteness was seen to degrade coherent, but not non-coherent structures(β= -0.050, t = -2.159, p< .05). Swedish showed no effect of finiteness or finiteness by coherence interaction.

Our results demonstrate that coherence improves extraction from adjuncts in both Swedish and English, which suggests that filler-gap association is not suspended in adjunct clauses. Furthermore, we show that finiteness reduces the acceptability of coherent structures, but only in English, thus pointing to one case of cross-linguistic variation.One possible explanation for this variation is that finite and non-finite adjuncts in English differ in terms of syntactic complexity: Non-finite after-adjuncts in English have a participial structure and can be assumed to lack a contentful CP-domain. Extraction from such structures thus requires fewer intermediate steps in successive-cyclic movement and a corresponding lower processing cost than extraction from their finite counterparts(see Wurmbrand, to appear, for a similar account for quantifier raising in English). In contrast, Swedish non-finite after-adjuncts involve a complementizer and an infinitive and can be assumed to be similar in structural size to their finite counterparts, requiring equally many movement steps and hence similar processing costs for extraction.

1) 

a. coherent | non-finite/finite

Which beer did he almost stumble [after chugging / after he chugged]?

b. non-coherent | non-finite/finite

Which beer did he stroll a little [after chugging / after he chugged]?

(2) 

a. coherent | non-finite/finite

Den medicinen däckade han alltid [efter att ha tagit / efter att han hade tagit].

that medicine fell-asleep he always after to have taken / after that he had taken

‘He always fell asleep {after taking/after he took} that medicine.’

b. non-coherent | non-finite/finite

Den medicinen stannade han lite [efter att ha tagit / efter att han hade tagit].

that medicine stayed he a little after to have taken / after that he had taken

‘He stayed a little {after taking/after he took} that medicine.’

Figure 1. z-adjusted ratings for Exp. 1 (English) 

Figure 2. z-adjusted ratings for Exp. 2 (Swedish)

References

Anward, J. (1982). Basic Swedish. In E. Engdahl & E. Ejerhed (Eds.), Readings on unbounded dependencies in Scandinavian languages (pp. 47-75). Stockholm: Almqvist & Wiksell.

Hagström, B. (1976). Om satsflätans förutsättningar. En skiss. In L. Svensson, A. M. Wieselgren, & Å. Hansson (Eds.), Nordiska studier i filologi och lingvistik. Festskrift tillägnad Gösta Holm på 60-årsdagen den 8 juli 1976 (pp. 138–150). Lund: Studentlitteratur.

Huang, J. C.-T. (1982). Logical Relations in Chinese and the Theory of Grammar. PhD. Dissertation, MIT, Cambridge, Mass.

Kush, D., Lohndal, T., & Sprouse, J. (2017). Investigating Variation in Island Effects: A Case Study of Norwegian Wh-Extraction. Natural Language & Linguistic Theory. doi:https://doi.org/10.1007/s11049-017-9390-z

Phillips, C. (2013). On the Nature of Island Constraints. II: Language learning and innateness. In J. Sprouse & N. Hornstein (Eds.), Experimental syntax and island effects (pp. 132-157).Cambridge: Cambridge University Press.

Sprouse, J., Caponigro, I., Greco, C., & Cecchetto, C. (2016). Experimental syntax and the variation of island effects in English and Italian. Natural Language & Linguistic Theory, 34, 307–344.

Traxler, M. J., & Pickering, M. J. (1996). Plausibility and the processing of unbounded dependencies: An eye-tracking study. Journal of Memory and Language, 35(3), 454-475.

Truswell, R. (2011). Events, phrases and questions. Oxford: Oxford University Press. 

Wurmbrand, S. (To appear). The cost of raising quantifiers. To appear in Glossa.