现在完成进行时的构成
肯定句：主语 + have/has + been + 现在分词...
否定句：主语 + have/has + not + been + 现在分词...
疑问句：Have/Has + 主语 + been + 现在分词...?
疑问代词/疑问副词 + have/has + 主语 + been + 现在分词...?
1、2 现在完成进行时的肯定句
句型：主语 + have/has + been + 现在分词...
现在完成进行时的肯定句由“助动词have/has + been（been是be动词的过去分词）+ 现在分词”构成：
I've been trying to find out her telephone number.我一直在查问她的电话号码。
They have been widening the road.他们在拓宽这条路。
She is very tired. She's been typing letters all day.她很累了。她整天都在录入信件。
