2 . He made another wonderful discovery. I think this discovery is of great importance to science.
→____________(改写复合句)

3 . Many teenagers spend too much time playing mobile phones. It is harmful to their health.(用which引导非限制性定语从句将两句话改写成一句话)

5 . Many teenagers spend too much time playing games.
It is harmful to their health. (用which引导的非限制性定语从句连接两个句子)
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6 . Robinson Crusoe reached a lonely island . He stayed on the island for 22 years. （合并成含有非限制性定语从句的句子）
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7 . Tom was late again. It made the teacher annoyed. (用非限制性定语从句改写)
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8 . We should protect our environment. It is of vital importance. (改写非限制性定语从句)
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