使用目前常用的算符优先法，对通用表达式计算过程进行了介绍，并对其中的关键问题——运算符优先矩阵的设计和实现进行了研究。
Using the current commonly used operator priority method, introduces a common expression of the calculation process, and one of the key issues, operator precedence matrix design and implementation.
文本表达是指将表达文献主题内容的词汇抽取出来的过程。 常用的向量空间表达法主要采用TF/IDF等权重法。
Text representation approaches with term weighting schemes such as commonly used TF/IDF are widely used to extract indexing terms of documents.
这些技巧他常常用得过分，显得晦涩，或过于微妙，难以理解，但是他用的新的同语和新的表达法丰富了英语。
He often ran to excesses, and became obscure or too subtle for understanding. But he has enriched the English language with new words, new turns of expressions.
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