first this paper introduces 本文首先介绍了

this paper introduces briefly 本文简要介绍了

this paper introduces several 介绍了几种

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this paper introduces in detail 本文详细介绍了

this paper introduces and analyzes 介绍和分析

this paper introduces and analyses 介绍和分析

this paper briefly introduces 本文简要介绍

this paper mainly introduces 主要介绍了