But you have no control over what MAC addresses will be in the devices you purchase, and you normally can't alter them, so it's impossible to organize anything by MAC address.

但当你买到一块网卡时却无法控制其MAC地址的值，而且通常你还不能修改它，这就会由它引出一些事情。

youdao

Medicare costs are more difficult to control, but not impossible.

Medicare的花销控制起来要难得多，但并非不可能。

youdao

But whatever the approach, without a point person to take control, effectively dealing with social media becomes nearly impossible.

但不管是何种方法，没有专门的人员来负责，要高效地处理社会化媒体关系几乎是不可能的。

youdao

Menasche's initial trial of the method on ten patients showed tantalizing hints of efficacy, but because there was no control group, it is impossible to tell whether the improvements seen were due to the cell transplant or to the bypass surgery the patients also received.

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The voters showed political independence and a willingness to make judgments apart from party, but it's impossible to draw grand conclusions about ideology, Al Gore, control of Congress or HMO reform from these outcomes.

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"It's possible to reinforce control on that border, but closing it is virtually impossible, " said analyst Mohamed Chafik Mesbah, a retired officer of the Algerian army.

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