1一般现在时主语+系动词标志词有often，usually，always等要注意“单三”，即hesheit2现在进行时主语+be动词+动词-ing形式标志词有now，atthistime3一般过去时主语+动词过去式标志词有ago,yesterday,thedaybeforeyesterday,lastweek,justnow等4过去进行...

时间:2024-10-26 12:05栏目:行业资料