Constructivism, the latest teaching and learning theory in western countries which is based on the premise that cognition (learning) is the result of 'mental construction', lays emphasis on the learner's active learning. Beginning with a brief account of its learning and teaching theory, the paper discusses its great implications for English language teaching-how to choose authentic materials, how to conduct a project-based and situational instruction and how to carry out a 2-side information delivery group work. It's obvious that constructivist-theory has great implications for the English la...