Первый ответ сделаю лучшим. укажите верный вариант ответа. 1 we knew that he is not able to made his work in time and decided to help him. 2 we knew that he was not able to make his work in time and decided to help him. 3 we know that he was not able to making his work in time and to decide help him. 4 we known that he was not able make his work in time and to deciding help him.
Ошибки:
№1 - не соблюдается правило согласования времен (ошибка - is)
№3 - нужен инфинитив (ошибка - making)
№4 - нет частицы to после able