The pillars have to support the________(weigh)of the roof．
他发现戒烟很难． ．
3D打印技术发展迅速，许多专家建议把这项技术介绍给更多的中学生．
The 3﹣D printing is developing fast．Manyexperts suggestthat it should be to more middle school students．
环境在日益恶化，人们必须开始采取行动改善它．
The environment is getting worse．People have to start to improve it．
生活充满挑战，我们应该怀最好的希望，做最坏的准备．
Life if full of challenges．We should hope for the best and the worst．
我的父母对我要求很严格，所以我有着良好的习惯．
My parents are very me，so I have good habits．