One of the most detailed reports on developmental patterns in learner English has been conducted by Thewissen (2013), who studied the development of accuracy in EFL learners using a learner corpus. The corpus included native speakers of French, German and Spanish, whose skills in English ranged from B1 to C2 on the CEFR11, the Common European
Framework of Reference for Languages (CEFR 2001). Using the corpus, she was able to explore where progress12 can be seen as learners become more proficient, which elements
remain stabilised and where the critical points of development lie on the CEFR scale. Her results show three main developmental patterns: a) the strong developmental pattern, where there is “a statistically significant difference in behavior between at least one pair of adjacent proficiency levels”; b) the weak developmental pattern, where there is a marked difference “between at least one pair of non-adjacent levels” and c) the non-progressive trend, where error types show “no significant behavioral change from B1 to C2” (Thewissen 2013, 83-84). In the following, I only discuss the error types that involve verb forms. They are listed in Table 3.
Thewissen’s study (2013, 85-88) indicates that within the strong developmental pattern (adjacent proficiency levels), the number of spelling errors, missing words, morphological 11 The CEFR is widely used these days to assess students’ language skills on a holistic framework. Although it
was originally intended for self-assessment, it has been applied for other purposes as well. For a discussion on the role of the CEFR in Europe, including some criticism, see Cook 2011. For aligning tests to the CEFR, see Papageorgiou (2016).
12 The CEFR itself avoids discussing grammar and focuses on communicative competence and on what learners
errors (leading to non-existent words) and errors in phraseological units decrease significantly when learners move from B1 to B2. In addition, this is the stage in proficiency development when verb number (verb agreement) errors, verb morphology errors and verb-dependent preposition errors markedly decrease. Although there does not seem to be statistically significant quantitative progress in these error types at levels B2 to C2, Thewissen (2013, 89) argues that there is qualitative progress, as students start taking greater risks and have command over increasingly complex patterns. Furthermore, in some cases significant learning has already taken place at the A levels, and the mean error percentage score may be minimal already at B1 (Thewissen 2013, 87).
Table 3. Developmental patterns in the acquisition of English verb forms based on Thewissen (2013)
Developmental pattern Feature Relevant progress in CEFR levels The strong developmental pattern spelling errors B1 to B2
missing words B1 to B2
morphological errors leading to a non-existent word
B1 to B2 errors in phraseological units B1 to B2 verb number (verb agreement) errors B1 to B2
verb morphology errors B1 to B2
verb-dependent preposition errors B1 to B2
adverb order errors B to C
The weak developmental pattern word order B1 to C1/C2
verb voice B1 to C1
modal auxiliaries B1 to C2
The non-progressive trend tenses -
verb complementation -
finite vs. non-finite verb forms -
In Thewissen’s study (2013, 89), only one error type shows improvement from the B macro- level to the C macro-level: adverb order errors. This means that significant increase in proficiency appears only when looking at the entire B vs. C level. Furthermore, C-level learners typically use significantly more adverbs than B-level learners, which seems to point to “simultaneous co-development between accuracy and complexity” (Thewissen 2013, 89) as students begin to use more complex forms and are more accurate in their use of previously
learned forms. Thewissen (2013, 90-91) also identifies some weak developmental patterns, with statistically significant development between non-adjacent proficiency levels. This includes word order, with improvement mainly from B1 to C1 and to C2, and verb voice, with increased mastery from B1 to C1. Interestingly, modal auxiliaries show significant improvement only from B1 to C2. This may be because modal auxiliaries have complex uses, often affecting larger elements than just their immediate surroundings in a sentence (Thewissen 2013, 91).
Finally, Thewissen’s (2013, 92) study includes error types that show no statistically significant improvement at all from B1 all the way to C2, despite some improvement. This group includes, for example, tenses, verb complementation and finite vs. non-finite verb forms. She notes that tenses remain a difficult part of English grammar, perhaps because students need to have command over both tense and aspect, and because tense choices often have implications over larger elements than single clauses (Thewissen 2013, 93). Furthermore, she thinks these error types may resist change because attempts at increased complexity do not show in the quantitative data. Thus, although students try to use increasingly advanced and complex forms and, hence, show signs of learning more, they may make more errors in using the more complex forms while becoming better at using the simpler forms they learned earlier, which results in similar scores in the number of errors despite improvements in quality (see also Storch 2015, 350). However, the total number of errors were small in both verb complementation and finite vs. non-finite verb forms, with mean error scores already below 0.5% at level B1 (Thewissen 2013, 92-93).
Based on the findings, Thewissen (2013, 94) finds further support for the argument that language learning is not a linear process (see Section 2.3.2): as a matter of fact, few error types showed only positive development. Several error types persisted with some progress and stabilisation, or with stabilisation only. The most marked development in accuracy took place between B1 and B2, which leads Thewissen (2013, 95) to suggest that this is a “possible accuracy threshold”, after which accuracy remains fairly stable. Nonetheless, while progress slows down between B2 and C2, it does not disappear (Thewissen 2013, 96). However, the study only included learners at levels B and C and does not discuss the development that takes place already before learners reach level B1. Furthermore, the study only included German, Spanish and French learners of English and does not account for potential differences with learners from other L1 backgrounds. While I do not attempt to place the students in this study on the CEFR scale, the expectation is that they would have reached level B2 (see Sections 5.2 and 5.3). For students’ command of verb forms in this study, see Chapters 7 and 8.
4.5 Summary
The English language poses challenges to L2 learners with its complex system of verb forms. In particular, the existence of regular and irregular verb inflection and the difference between simple and progressive forms may be difficult for learners. In addition to morphology, learners need to understand the appropriate contexts for particular forms, which is challenging even for advanced students. Genre-specific requirements, such as those in academic writing, pose further challenges. In particular, learners may struggle with tense, aspect and the passive. Further instruction would make L2 writers more credible as academics and help them follow the conventions of academic writing.
Research shows that there may be a hierarchy in the order of acquisition of verb forms, which is partly universal and partly dependent on the L1. For example, progressive forms take longer to stabilise than simple forms, and they may remain limited to the prototypical uses for a long time. Nevertheless, the increasing uses of the progressive imply that a greater range of uses is likely in both L1 and L2 English in the future. Generally, learners tend to associate verb types with particular forms, for example the progressive with activities and the simple with telics. Furthermore, the progressive is more common when providing the background in narratives, while the simple is more common in the foreground. The learner’s L1 also influences which forms are difficult to acquire.
In English, a number of verb forms and uses can take a long time for learners to master. In some cases, significant improvement only appears at the C1 or C2 levels on the CEFR grid. However, the learning process is not linear, and learners may make quantitatively more mistakes when they produce qualitatively more complex structures. The major threshold in accuracy seems to be between B1 and B2.