1--We need to take the accounts system offline to carry out the upgrade. But don't worry, it won't cause too much inconvenience. We're going to do it over the weekend.
 
2-- How long will the system be down for?
 
1-- We'll be taking everything offline in about two hours' time. It'll be down for a minimum of twelve hours. If everything goes according to plan, it should be up again by 6 pm on Saturday.
 
2--That's fine. We've allowed forty-eight hours to be on the safe side.
 
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注解：
 
1.upgrade升级
2.inconvenience不便
3.minimum 最小值
 
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译文：
 
1--我们需要把这个报账系统下线进行升级但是别担心，不会带来太多不便的。我们在本周末进行升级。
2--这个系统多久能够下线？
1--全部下线需要两个小时的时间。至少需要12小时才能弄完。如果一切都在计划之中，在星期六应该可以再次上线。
2--行。我们要求四十八小时安全可靠。