The need to communicate is a key characteristic of human society.
需要交流是人類社會最重要的一個特征。
Cost was a key element in our decision.
價錢是我們決策時考慮的主要因素。
Good communication is key to our success.
良好的溝通是我們成功的關鍵。
These units played a key functional role in the military operation.
這些單位在軍事行動中起到了主要的職能作用。
The president appears likely to change course on some key issues.
總統看起來可能要在某些重要問題上改變方針。