tom often helps his mother at home

tom often helps his mother at home

What does Tom often do at home.追答
追答：What does Tom often do at home？
追问：为什么加do14、对“做什么”提问用what…do /doing/done.如：
(17).They are going to visit the factory next week.→ What are they going to do next week?
(18).You are looking at the blackboard.→ What are you doing?
(19).They have seen the film.→ What have they done?有缺省的词情况的变化：
有缺省的词时要注意固定句型的准确选择和运用:
(1.)She played soccer last night.
What did she do last night?
(2.)He is a student.
What does he do?
(3.)Tom is looking at the picture.
(4.)What is Tom doing?
(5.)Lucy is of medium height.
What does Tom look like?不是很能理解这些是为什么这个补充的do
追答：对于动词的疑问句以及反问句，动词仍然在主语之后，将助动词do提前。前面的does是助动词，只是形式，没有实际意义。后面的do是实意动词，意思是“做，干，从事，进行”的意思。