Ответ:
Упр. 4
1) am writing
was writing
2) is sleeping
was sleeping
3) are not doing
are playing
4)were not doing
were playing
5) are ... doing? I am drinking tea.
were ... drinking?
was not drinking, was eating a banana.
Упр.5
устал писать ;)
Объяснение:
Если указывается точное время ( например, вчера в 7 утра, завтра в этот момент и т. д.), то употребляется презенет континиус.