The boy has been interested in .for a few years 为什么用has been
问题描述:
The boy has been interested in .for a few years 为什么用has been
答
.for a few years 表示一段时间
与一段时间连用的时态 一般就是现在完成时 have/has +动词的过去分词
其中be interested in 是对.感兴趣
be 的过去分词就是been
所以是has been