Another Piece of the Puzzle: The Emergence of the Present Perfect.

Previous research has shown that the acquisition of morphological form in the tense-aspect system is relatively trivial compared with the significant acquisitional task of developing a target-like association of form with meaning (Bardovi-Harlig, 1992a, 2000; Bardovi-Harlig & Reynolds, 1995). This pattern is not restricted to instructed learners, however (cf. Dietrich, Klein, & Noyau, 1995). Nevertheless, recent studies have undertaken to understand the role of instruction in the development of the interlanguage tense aspect system. Studies of the influence of instruction on the development of interlanguage tense-aspect have utilized both experimental and observational designs. The experimental studies typically compare a treatment group with an in-structed group that did not receive the same treatment. Experimental studies in this area have included French and Spanish as well as English. Harley (1989) employed a functional approach that focussed on discourse, in which student output focused on both form and content. Cadierno (1995) compared processing instruction-providing explicit intervention in the processes and strategies used by L2 learners of Spanish in processing input-with traditional instruction and with no focused instruction on the past. A study of the effects of a focus-on-form approach on the use of the preterit and imperfect in Spanish in a communicative Spanish classroom was conducted by Leeman, Artegoitia, Fridman, and Doughty (1995). Doughty and Varela (1998) investigated the influence of communicative focus on form (the English simple past and would) in the interlanguage of learners enrolled in a middle-school ESL content-based science class. Bardovi-Harlig and Reynolds (reported by Bardovi-Harlig, 1995) conducted an instructional experiment employing input enhancement through focused noticing and accompanying production exercises. On the one hand, experimental studies exercise control on many variables; but on the other hand, they are also often relatively brief in duration of instruction (but see Harley, 1989, and Doughty & Varela, 1998, for exceptions) and are often limited in terms of the language samples collected from the learners. The second type of study is observational. In this type of study, there typically is no control group, but the individual learners are compared with themselves before and after periods of instruction lasting approximately a year. These studies overcome the focus on short-term effects that tend to characterize the experimental studies. It is to this type of inquiry that the present study belongs. The following article addresses the acquisition of the present perfect by classroom second language learners during up to 15 months of intensive English language instruction and is part of a larger investigation of the influence of instruction on the tense-aspect system as a whole. (See also Bardovi-Harlig, 1994, for a discussion of the pluperfect; Bardovi-Harlig, 2000, for past progressive, present perfect, and pluperfect.) Extended observation, such as that conducted in the present study, that does not restrict the environment of use for a learner allows observers t o see the development of interlanguage as learners incorporate (or do not incorporate) instructionally targeted forms into their interlanguage as they are engaged in communication. Extended observation also reveals that the learners have individual acquisition profiles, especially with respect to rate, in spite of the fact that they are enrolled in the same intensive English program. In spite of the advantages of observational studies, it may be more difficult to determine the effect of instruction in an observational inquiry than in an experimental study The learners in this study were completely in control of their own production in terms of both topic and, a t least for the journals that were the major source of data, whether or not they produced a language sample. Thus, the control the researcher has-and the resulting comparability of the language sample-is reduced. The siriiultaneous focus in SLA research on tense-aspect development has encouraged an acquisitional perspective in both types of instructional-effect research as well. In the tense-aspect instructional research, as in the tense-aspect acquisition research, progress is interpreted not merely as target-like use-which represents the endpoint of the acquisitional process-but advancement along the acquisitional sequence. When success is seen as progress rather than perfection, the many positive effects of instruction are revealed.