Thai EFL learners' comprehension and production of English if-conditionals

This study sought to determine which conditional verb forms proved most difficult for Thai secondary school students to understand and produce, as well as what errors resulted in written and spoken English. The participants were 68 twelfth grade students in an integrated English program at a public high school in Bangkok, Thailand. The data was collected by a comprehension task to determine the Thai learners’ comprehension of English conditional verb forms; a gap-fill task to examine students’ production performance and conditional errors in written English; and a spoken task to explore the performance and errors of 20 students. The results of the comprehension task were that Thai English as a foreign language (EFL) students found Future Predictive Conditionals most problematic and Present Counterfactuals easiest to understand. In the gap-fill task, the participants scored highest in Future Predictive Conditionals and lowest in Past Counterfactual Conditionals. The spoken task results concurred with the written ones. In the gap-fill task, the present simple tense accounted for the most errors in linguistic taxonomy, while misformation errors were most frequently produced in surface structure taxonomy. In the spoken task, the future simple tense was most commonly misused in linguistic taxonomy, while omission errors were most frequent in surface structure taxonomy. The pedagogical implications are provided in the study.