Это правильный глагол, поэтому к нему добавляем только -ed, и так же в случае слова drop, буква Р удваивается. Получаем:
Drop-dropped-dropped.
Аня и мама Джерри пошли играть в теннис
Во вложении))мне 11 поставили
It had been snowing for 4 hours
Eton had been working for 20 years before he retired
Mike had been living there for a tonight
They had been studying German for 5 years before they went to Berlin
The authors had been working on the novel for 2 years before the sent it to a publisher
Pele had been playing football for 6 years before...
The students had been listening attentively to the dialog for an hour ...
The children had been walking for 2 hours..
(вместо точек просто продолжение предложения без изменений)
Tiny didn't write songs for pop-singers last year.
Billy isn't be in Antarctica three years ago.
The boy didnt drink cold and dirty water yesterday .
Jill didn't play football an hour ago.
Tim and Tom aren't be in the desert a week ago.