助动词do,did,does
情态动词：can,may,must,should,could,might,shall等
感观动词：look,listen,hear,see,watch,feel后表看到,听到整个动作过程的时候接动词原形
suggest,request等后面接虚拟语气形成suggest...should do sth.时用动词原形
还有will,be going to,used to等
助动词do,did,does
情态动词：can,may,must,should,could,might,shall等
感观动词：look,listen,hear,see,watch,feel后表看到,听到整个动作过程的时候接动词原形
suggest,request等后面接虚拟语气形成suggest...should do sth.时用动词原形
还有will,be going to,used to等