Even though the bottle is tightly stoppered, the scents will be evaporated after a long time. 只有巧妙利用香水，才能讓你在不同場合，扮演各種不同的角色，發揮你的魅力。
Of course, many problems recur at various periods. 當然，有許多問題會在不同的時期反覆提出。
She has devoted herself to an extensive variety of public subjects, at various time, and is at present devoted to the subject of Africa. 她在不同的時期，熱心研究過種種不同的公共問題，目前，正致力於非洲問題。
