III :
3.was
4.is
5.is
6.are
7.are
8.are
9.is
10.are
IV:
1.am -> was
2.were -> was
3.were /thứ 2/ ->are
4.was -> were
5.was -> were
V:
1.How was she yesterday ?
2.Where were you last night ?
3.When were they in Ha Noi ?
4.When was Peter a student ?
5.Where was your sister last month ?