第1个回答 2020-03-09
did是助动词do和does的过去式,而was/were是be动词am、is/are的过去式。
一个句子中,如果没有be动词,发生动作要用助动词do或does.
例如:i
am
a
student.
问句是:are
you
a
student?
有be动词所以直接用are提问。
i
worked
in
an
international
company
2
years
ago.
句中没有be动词,所以要用助动词代替,问句是:
did
you
work
in
an
international
company
2
years
ago?