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- Most certificates don't need to be backed up. 大多数证书都不需要进行备份。
- The lectures and seminars of the course are to be backed up by a heavy program of field work. 这门课程除讲课和讨论外，还有大量的实地调查作为补充。
- The lectures of this course are to be backed up by a comprehensive programme of field work. 这门课程除了讲课外，还有综合性的现场实习加以补充。
- When to be Backed up 可当后盾
- I had better hit the road if I'm to be back home before dark. 如果我要天黑前到家，我最好现在就动身。
- The party expects to be back in power after the election. 该党希望大选以後能重新掌权。
- It is my best time when to be with you. 和你在一起的时间是最快乐的时候。
- If I went with her, I'd have to be back by five o'clock. 假如我和她一起去的话，我就得在五点钟以前回来啦。
- I want you to be back before the day is done. 我要你在天黑前回来。
- I expect to be back next Monday. 我预计下星期一回来。
- We hope to be back by nightfall. 我们希望傍晚时能回来。
- Want to be able to back up or restore just that site. 希望能够只备份或还原该网站。
- He who knows when to speak will also know when to be silent. 知道什么时候该讲话的人，也知道什么时候沉默。
- You've to be back by ten o'clock,mind. 注意，你得在10点以前回来。
- OK,but I've got to be back before 11 p.m. 好吧，不过我得在晚上11点前回来。
- What time is he expected to be back? 他预定什么时间回来呢?
- What time is he supposed to be back? 他打算什么时间回来呢?
- One who knows when to speak will also know when to be silent. 知道什么时候应该讲话的人,也知道什么时候应保持沉默。
- A good boss knows when to be hard on his employeees. 一个精明的老板知道何时应对员工严格要求.
- I really must go now. I'm expected to be back soon. 真的该走了，我必须早点儿回去。
