Our country______a lot in the last fifty years该怎么填?A.changed B.changes C.has changed
问题描述：
Our country______a lot in the last fifty years该怎么填?A.changed B.changes C.has changed
He______[have] to walk to school every day该怎么填？
答
Our country__has changed____a lot in the last fifty years
He has to walk to school every dayWhat上面选C下面填has为啥 大神帮帮我为啥问为啥呢？ 英语语法规定是这样啊，约定俗成的. 第一个是现在完成时，第二个是第三人称变has