1. 当有利时：as occasion requires 在必要时 | as occasion serves 当有利时 | as of old 依旧
2. 一有机会就：56、as much as to say ......等于说 | 57、as occasion serves 一有机会就 | 59、as often happens 如同经常发生那样
3. 一有机会,一有适当时机,方便的时候：as follows 如下 | As occasion serves 一有机会,一有适当时机,方便的时候 | As the matter stands 按照现状
4. 一有适当的时机：as occasion requires 遇必要时 | as occasion serves 一有适当的时机 | as occasion offers 有机会时, 机会到来时
1. I'll do it as occasion serves.
只要有适当的机会我是会干的。
2. Therefore, the convention should be amended as occasion serves and its contents should be improved so as to accommodate the current circumstances of space activities.
因此，应当在适当的时机对公约加以修订，完善公约的内容，以使其适应空间活动的现状。
3. Once more, a natural disaster serves as an occasion to showcase the impoverishment, to exaggerate the scenes of violence that are common to any 15catastrophe of this type.
又一次，一场自然灾害被用作一次机会来展示当地的贫苦，夸大同类大灾难下普遍会有的暴力场面。
4. Government needs an appropriate orientation to exercise in the process of specialized towns'economic growth, -actively intervenes at the initial stages and fades out as occasion serves.
专业镇经济是中山经济竞争的重要载体与组成部分，各级政府在专业镇与组团经济发展过程中发挥着极其重要的作用。
5. Government needs an appropriate orientation to exercise in the process of specialized towns'economic growth, - actively intervenes at the initial stages and fades out as occasion serves.
专业镇经济是中山经济竞争的重要载体与组成部分，各级政府在专业镇与组团经济发展过程中发挥着极其重要的作用。
6. Once more, a natural disaster serves as an occasion to showcase the impoverishment, to exaggerate the scenes of violence that are common to any catastrophe of this type.
又一次，一场自然灾害被用作一次机会来展示当地的贫苦，夸大同类大灾难下普遍会有的暴力场面。