At present, the terms of business, education, science, and technological progress have been presented by new technology and the adoption of the Internet which almost in English, so it is necessary to have high English proficiency to communicate (Wiriyachitra, 2002). With the opening of the AEC (ASEAN Economic Community) in 2015, MPN inter-trade reported on December 6th, 2012 that Thailand had great opportunities to grow with tourism and travel, international business and foreign investments, and access to more labor. Also, it will expand Thai agricultural shipments in the region. Moreover, Bangkok post stated on September 17th, 2013, “The government will reform Thailand economically to ensure its readiness to cope with competition among ASEAN countries and rapid change globally,” the Prime Minister said. However, Darasawang (2007) indicated that during the reign of King Rama V, English became the most prestigious foreign language when many foreigners visited Thailand, creating a greater need for English. King Rama V believed that the modernization and progress of the country required more Thais to study foreign languages and be educated abroad. Therefore, English language is international language as a working and learning language, so improvement Thai students in English ability is to enhance their chance to work and study efficiency.