解释：大部分药材都以新鲜为好，但艾草却以陈年的为佳，体现了药材使用的特殊性。
The people are the government, administering it by their agents; they are the government, the sovereign power.
The spread of liberal democracy and the integration of the world economy have created a situation in which the major powers are no longer willing to risk war with one another.