The difficult thing with this 'natural' dose is that it is continuously changing. It is therefor impossible to choose a set number as a limit. The limit is better formulated as 'as small as possible'.
但是这些“天然”的辐射量在经常改变，因此我们很难选择一个数目作为限制量，而最好的辐射量限制也许说为“最小剂量”可能更合适。
The purpose of property management bidding is to choose the best proposal, but the particularity of this profession makes the bidding process difficult.
物业管理招标的目的是选择最合适的方案，但由于其行业的特殊性，造成了评标工作的困难。
The purpose of property management bidding is to choose the best proposal, but the particularity of this profession makes the bidding process difficult.
物业管理招标的目的是选择最合适的方案，但由于其行业的特殊性，造成了评标工作的困难。
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