United, there is little we cannot do in a host of cooperative ventures. Divided, there is little we can do — for we dare not meet a powerful challenge at odds and split asunder.
All of these issues are rooted in the fact that no one nation can meet the challenges of the 21st century on its own, nor effectively advance its interests in isolation.
Let us also start anew in the vitality of spring, let us meet new challenge with brand-new posture, embark on a new journey, embrace the fruitful sunny summer!
Human capital is more of a challenge. Americans once led the world in educational attainment, but this is now barely rising while other countries have caught up (see article).
Sit down to read and the flywheel of work-related thoughts keeps spinning—or else you're so exhausted that a challenging book's the last thing you need.