What are the three kinds of learning and teaching materials in u

What are the three kinds of learning and teaching materials in use by teachers adopting the Communicative Approach?
【正确答案】：They are text-based materials, task-based materials and realia.
全题共5分,答案含三点,第一、二点每点2分、第三点1分。如答案要点不完整,酌情扣分。如表述有语法、拼写、标点等问题,也酌情扣分,但全题在这方面的扣分不得超过1分。