2 r; C1 D! c7 UTheory is when you know everything but nothing works. , k: l6 @3 N T7 O0 \/ f. ^( R5 `& n% n
Practice is everything works but no one knows why.$ h7 p% p" A7 j8 K. t
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这两天的情况是:Theory and practice are combined: nothing works and no one knows why.