In the context of Vietnam’s extensive international integration, economic concentration emerges as a pivotal strategy employed by businesses across various sectors, notably the retail industry, to foster expansion and bolster competitiveness within the market. As this trend evolves, it necessitates the formulation by the Vietnamese Government of a comprehensive and stringent legal framework tailored to regulate economic concentration among enterprises. Such measures are imperative to preclude the curtailment of market competition, which could potentially undermine the equity and vitality of the business environment in Vietnam. This paper meticulously examines and elucidates theoretical nuances surrounding economic concentration in the retail sector. Additionally, it scrutinizes the current landscape, assessing the impact of extant legislation governing economic concentration and the efficacy of enforcement activities in this realm within the Vietnamese retail sector. Consequently, the paper proffers judicious recommendations to enhance the efficacy of legal mechanisms governing economic concentration to foster competition and fortify Vietnam’s overall economic prowess, particularly within the retail sector.

Tennis, as an important project of sports, has an obvious role in cultivating students' physical quality, observation ability and reaction speed. Under the background that the country attaches great importance to students' physical literacy, the traditional single and passive teaching has been unable to meet the practical needs, so it is necessary to strengthen the innovation of teaching methods. With the recognition of many teachers, the teaching method of "combining competition and practice" has been continuously promoted. The paper takes the combination of competition and practice as the teaching mode, and studies the teaching of college tennis sports.

The global climate governance process will have a profound impact on geopolitical relations, and, at the same time, these will determine the direction of cooperation in international climate governance. The European Union and the United States are the most important players in the global governance of climate change, and their competing policy orientations and dynamics have a major impact on trends in this field. In this context, Africa is the region most vulnerable to climate change, and the climate issue in Africa has become one of the frontiers of competition between major powers. Indeed, major powers are increasingly competing in Africa, primarily in the areas of climate leadership, program provision, and capacity building. The study is based on the review of articles and research works regarding the global climate change strategies, especially in AFRICA (2020–2024); it also collected information and statistics from the websites and reports of world banks. In the future, the European Union and Africa should work together to build a new era of strategic partnerships to fight climate change. To do this, they should strengthen their strategic collaboration in global climate governance, look for new ways to work together in old ways, and make their cooperation more effective and efficient.

Sports competition is one of the important contents and forms of sports activities and physical education. It plays a full range of valuable functions in promoting the all-round development of college students. Specifically, it can better help college students enjoy fun, enhance their physique, and improve their physical fitness during physical exercise. Personality and tempering the will. Countries around the world attach great importance to youth sports competitions, and use national strategies as the top-level design and sports events as activity carriers to create a series of youth sports competitions such as graded competitions, championships, and campus events, providing more opportunities for young people to watch and participate in sports. Opportunities and platforms for competition. College student sports competitions are an important part of youth sports competitions and shoulder multiple missions such as physical health promotion, competitive talent training, and sports industry development. In recent years, the development of college sports competitions around the world has achieved remarkable results, and the scale and quality of Chinese college sports competitions have also been significantly improved. However, compared with developed countries, overall, there is still a weak awareness of participation, poor competition experience, and competitive competition. Prominent problems such as low levels and high activity withdrawal rates have, to a certain extent, restricted the high-quality development of college student sports competitions. In fact, it is not as easy as imagined for college students to participate in sports competitions regularly for a long time. In addition to requiring college students to possess certain basic conditions such as time, energy, and skills, it also requires support and promotion from all walks of life, especially It is inseparable from the material, spiritual and technical support provided by family, friends, coaches and other important groups. Just as the social ecological model believes that individual physical activity behavior is closely related to social support at the interpersonal level, especially social support from important groups such as family and friends has a positive impact on individual physical activity behavior. At the same time, although social support is very important, not all social support received can promote college students to form good sports competition behaviors. Self-determination theory emphasizes that only effective social support can regulate and optimize individual sports motivation by meeting the individual’s basic psychological needs, and ultimately promote the formation of positive, long-term sports behavior. However, most of the current sports academic circles continue the research context of traditional college student sports management, focusing on the contemporary value, practical issues, system construction, etc. of college student sports competitions. They are more subjective qualitative theoretical research and relatively lack the influence of social support. Empirical research on the sports competition behavior of college students, so that the internal mechanism of social support affecting the sports competition behavior of college students is not clear enough and understood. Therefore, from the perspective of social ecology, this study explores the internal mechanism of social support affecting college students’ sports competition behavior, in order to provide certain theoretical reference for improving the level of college students’ sports competition behavior.