1.频率副词是表示与次数,频率有关的副词,如:
always(总是), usually(通常),frequently(经常) often (经常)sometimes(有时), seldom(不常),rarely(极少),never(从不) once(一次), twice(两次),等。
2.频率副词等级 :
all the time 100%;
almost , always 90%;
generally , usually 80%;
often , frequently 60-70%;
as often as not 40-50%;
sometimes , at times 20-30%;
occasionally , from time to time 10%;
hardly , seldom , rarely 5%;
never 0%。

以上来自百度百科,希望能帮到您!