youdao

For middle school students to push other learners in their class is something completely new to most of them and getting them to see the value of this difficult task is not easy.

对于中学生来说，想让他们对其他学习者施压是完全新鲜的事情，让他们认识到这项艰巨的任务的价值也并非易事。

youdao

New class s (Storm) planet. This planet will be the most difficult planet in the game, and it will require 12 milestones to unlock.

新的等级s(风暴)星球。这个星球将会成为游戏中最难的星球，同时它需要12个里程碑来解锁。

youdao

"We have just come through what was one of the most difficult decades the middle class has ever faced a decade in which median income fell, and our economy lost about as many jobs as it gained,".

VOA: standard.2010.01.25