Knowing what you should strive to understand and how it applies, and more importantly how you can use it practically.

知道你应该努力有什么理解和如何适用，而更重要的是如何使用它实际。

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We must have a massive knowledge of not only what the law says but how to practically use that law and interpret it.

BBC: Is crime being tackled properly?

Mr Muglia clarified his comments in a blog post saying that exploding use of e-readers, tablets and different sorts of smartphones now made it "practically impossible" to get something like Silverlight running on all those devices.

BBC: Coders decry Silverlight change