has或havebeen怎么用？都是什么意思？它跟过去完成时是一?
has 是第三人称做主语时have的谓语变形，用于一般现在时态。例如：She has a book. He has an apple. It has a leg 而have been 是现在完成时态，是已经完成的动作。例如： We have finished our homework。