The true cost of coal must account for both its immediate value and its long-term impact on communities and ecosystems.
市場(chǎng)設(shè)計(jì)是一個(gè)持續(xù)的實(shí)驗(yàn)——今天有效的明天可能就需要調(diào)整。
計(jì)算復(fù)雜性的美在于它能夠根據(jù)問(wèn)題的固有難度對(duì)問(wèn)題進(jìn)行分類。
The secret of getting ahead is getting started.
Sustainability isn't a choice anymore—it's a responsibility we owe to future generations.
在認(rèn)識(shí)到熱是運(yùn)動(dòng)的一種形式后，沒(méi)有人會(huì)懷疑熱可以轉(zhuǎn)化為機(jī)械效應(yīng)。