always 总是
often/usually 经常
sometimes 有时,如：Joan goes to school on foot,but sometimes by bike.Joan走路去学校,但有时骑车.
some time 一段时间,如：I'll stay here for some time.我会在这里呆上一段时间
some times 倍、次,如：Our school is some times larger than theirs.我们的学校比他们的大几倍.
sometime 某时,如：Kate'll will be back sometime in February.Kate 会在二月的某个时候回来.
never 从不