1 . In 2017, r______ (代表们) from Peking University, Tsinghua University, Nankai University and Yunnan Normal University gathered to commemorate the 80th anniversary of its founding. (根据中英文提示单词拼写)

2 . Learning s______ (策略) are defined as approaches that learners employ to accomplish academic tasks. (根据中英文提示填空)

3 . Excellent ________ (展览) show how animals and plants are displaced by urban growth and the consequences of pollution. (根据汉语提示单词拼写)