现在完成时与一般现在时加频度时间副词时的区别?
现在完成时和一般现在时一样可以加频度副词,那么他们的区别在哪?比如说“我经常在公园看见他.”英文怎么说?是“i often see him in the park.”还是“i have often seen him in the park.”或者两者都可以?有什么区别?另外,they have always answered my letters.可以用they always answer my letter.为什么?