The knowledge society requires life-long learning and flexible learning environment that enables fast, just-in-time and relevant learning, aiding the development of communities of knowledge, linking learners and practitioners with experts. Based upon semantic wiki, a combination of wiki and Semantic Web technology, this paper designs and develops flexible e-learning environments for different application scenarios aiming to facilitate collaborative knowledge construction and maximize resource sharing and utilization. One application scenario is to support hybrid learning by deploying an online course platform and the first round of using has shown that the course platform can effectively facilitate and support students to fulfill task-driven learning in a more flexibly and friendly collaborative manner. The other application scenario is to build a teamwork platform for supporting collaborative e-research. After several months' trial, team members agree that the platform can well meet their collaborative research work demands with the advantage of quick, easy and convenient operating assistance. The kernel idea of the collaborative e-learning environments is to enable structural organization of resources with semantic association while providing diverse customized facilities. (Contains 2 tables and 14 figures.)