The document summarizes a study on the relationship between extroversion-introversion and English proficiency among Applied Foreign Language students in Taiwan. The study aims to investigate whether extroverts perform better on TOEIC tests than introverts and whether they use different learning strategies. It provides background on definitions of personality types and gaps in previous research on this topic. The methodology section indicates the study will use MBTI questionnaires and collect demographic data to analyze relationships between personality types and English performance.