(B C)26.They have known each other___.(复选) A.from last year B...答:主句中时态是现在完成时, have known , 时间状语要注意了。现在完成时态的标志词如下:since+时间, for + 时段, already(肯定), yet(否定,疑问), just, before, recently, recent years, these days/years, still, lately, in the past few years, ever since, in the last five ...