4. Сделай предложения отрицательными (4 балла)

Решение:

• They were happy. → They were not happy. (Для образования отрицания в Past Simple с глаголом 'to be' добавляем 'not' после глагола.)
• He wrote a letter. → He did not write a letter. (Для образования отрицания в Past Simple с другими глаголами используем 'did not' + инфинитив глагола.)

Ответ:

• They were not happy.
• He did not write a letter.