|Abstract:||In second language (L2) learning scenarios in which learners have to learn a linguistic phenomenon that exists in the L2 but is absent in the L1, input informing learners that the phenomenon exists in the L2 is crucial for learning. The effects regarding the form in which the input is delivered to learners, through naturalistic exposure or different types of instruction, have been an important topic in second language research. Explicit instruction has been found to induce immediate and long-term learning effects in L2 learning (e.g. Norris & Ortega, 2000; Spada & Tomita, 2010). However, some researchers argued that L2 instruction can only lead to explicit/learned knowledge, which is different from the knowledge native speakers possess (e.g. Krashen, 1981, 1982; Schwartz, 1993). Following this line of research, the goals of this dissertation were to examine different types of exposure/instruction on L1-Mandarin L2-English learners’ acquisition of inverse scope, which is a linguistic phenomenon that exists in English but is absent in Mandarin, and to examine the knowledge learners gain.
In this learning scenario, L1-Mandarin L2-English learners need input informing them that inverse scope exists in English. However, Chu, Gabriele & Minai (2014), the only study identified with this population prior to the present research, found that intermediate and advanced learners in Taiwan still faced difficulty in learning inverse scope from naturalistic input. Since the inverse scope is dis-preferred by English native speakers, and that inverse scope is not taught in language classrooms, it is possible that the relevant input in an English as a Foreign Language (EFL) environment is insufficient for learners to succeed. Therefore, this dissertation considered three possible solutions: (i) more naturalistic input (with learners being in a whole English environment such as in the U.S., which should expose them to more English input, compared to being in an EFL environment); (ii) input flooding (exposing learners to artificially-increased input); (iii) explicit instruction (teaching learners explicitly about inverse scope). The three solutions were examined in the three experiments in this dissertation, with naturalistic input being examined in Experiments 1 and 2, while input flooding and explicit instruction is examined in Experiment 3. The effects of input flooding and explicit instruction were further examined by measuring learners’ knowledge through three methods: (i) implementing debriefing questionnaires; (ii) collecting learners’ confidence ratings in language tasks; (iii) testing learners’ generalization of L2 knowledge.
The findings from Experiments 1 and 2 showed that intermediate-to-advanced learners in the U.S. still failed to acquire inverse scope, indicating that the naturalistic input containing inverse scope in a whole English environment is still insufficient for learners to succeed. Building on the baseline performance of this learner population from the previous two experiments, the findings from Experiment 3 showed that there was only a slight and short-term improvement with the learners receiving input flooding. On the other hand, the learners receiving explicit instruction showed significant improvement in their knowledge of the inverse scope, and the knowledge was still retained one month later. However, the knowledge was only restricted to the structure on which learners were instructed: learners only allowed inverse scope with the structure they were taught and did not generalize the knowledge to an untaught structure that also allows inverse scope. Moreover, learners even incorrectly generalized the knowledge to a structure that is similar at the surface yet does not allow inverse scope.
Overall, the findings indicate that explicit instruction is more effective than input flooding in L2 acquisition of inverse scope. However, results with generalization show that despite learners receiving explicit instruction gained knowledge of the inverse scope, the knowledge was restricted and not target-like. The findings thus conform with previous literature that explicit instruction induces an immediate (and potentially a long-term) effect in L2 learning, albeit learners’ knowledge is not native-like, supporting the argument that explicit instruction does not lead to native-like knowledge.