1 . 塑料需要几百年才能分解，但纸张分解所需的时间则要短得多。
________, but much less time for paper.

2 . 为了远离这些病毒的危害，建议我们应该养成健康的习惯。(it作形式主语)
To stay away from the harm of these viruses, ________________.

3 . 最重要的是，要想成为一名聪明的在线学习者，需要自律才能抵制所有在线干扰。
Most importantly, ________________ towards a smart online learner.(it takes sth to do)

7 . it作形式主语
教材原句：However，it is important to remember that they are only meant for guidance.
仿写：一个人做点好事并不难，难的是一辈子做好事。
　___________________   a bit of good, but it’s a struggle to do good for a lifetime.

8 . 据宣布，这家公司的首席负责这项慈善事业。
________________the chief of the company is in charge of the charity.