This thesis imparts the outcomes of a seven-week long quasi-experimental study that explored whether or not L2 learners who received intensive and highly focused indirect feedback on one type of treatable error - either the third person singular -s, plural endings -s, or definite article the - eventually become more accurate in the post-test as compared to a control group that did not. The paired-samples t-test comparing the pre-test and post-test scores of both groups demonstrates that the experimental group did no better than the control group after they received indirect corrective feedback. The independent samples t-test measuring the experimental and control group's accuracy shows no significant difference between the two groups. Effect sizes calculated, however, do indicate that, had the sample sizes been bigger, both groups would have eventually become more accurate in the errors targeted, although this would not have been because of the indirect feedback.

Second language (L2) researchers and teachers have increasingly come to believe that using a computer-based corpus can be extremely helpful in the language classroom. The purpose of this study is to examine whether corpora can be used outside of the classroom in order for students to improve their essays independently. No previous study has tried to examine students' essays in relation to corpus use so that this study is exploratory. Seven international students wrote five essays on specific topics and then corrected their errors through corpus research. Two experiments were conducted with different students and followed three steps: receiving information about how to use the BYU COCA, writing and correcting, and interviews with students. I examined quantitatively the number and types of errors that students were able to correct in two experiments and reported qualitatively on students' interview responses.