每一块曾经制造的塑料仍然存在于地球的某个地方——这既是我们的挑战，也是我们的责任。
Every piece of plastic ever made still exists somewhere on this planet—that's both our challenge and our responsibility.
User needs are both the starting point and the ultimate goal of product development.
关于理论最重要的事情是它应该是可测试的。