Помогите пожалуйста с предложениями в Past Simple , их нужно сделать +, ? , -.
We (read a book ) yesterday.
She ( help my brother) 3 days ago/
He (draw a picture) last month.
They(write a letter) last week.

1.We read a book yesterday. 
We did not read a book yesterday
Did we read a book yesterday?
2.She helped my brother 3 days ago
She did not help my brother 3 days ago 
Did she help my brother 3 days ago?
3.He drew a picture las month.
He did not draw a picture last month
Did he draw a picture last month?
4. They wrote a letter last week
They did not write a letter last week
Did they write a letter last week?