情态动词和频率副词哪个应在前

He can often play the piano.
频率副词放在情态动词,助动词,Be动词之后,实义动词之后.
1.频率副词是表示与次数,频率有关的副词,如:
always(总是),usually(经常),sometimes(有时),seldom(不常),once(一次),twice(两次)等.
2.频率副词用在be动词后.
It is usually hot in summer.
夏天天气通常是热的.
3.频率副词用在主要动词前.
My father usually walks home.
我的父亲经常步行回家.
4.频率副词用在助动词与主要动词之间.
I will always love you.
我将永远爱你.
5.频率副词用在OUGHT TO之间.
You ought often to write to your mother.
你应该常给你母亲写信.
6.在答句中,频率副词必须放在助动词前.
Do you often go there?
你常去那里吗?
(误)Yes,I do often.
是的,我常去.
(正)Yes,I often do.
是的,我常去.
7.never(从不),seldom(很少,不常)用于句首时,句子要用倒装形式以加强语气.
Never have I been there.
我从未去过那里.
Seldom do I watch TV.
我很少看电视.