2. Helen (to play) computer games from two till three yesterday.
В задании необходимо употребить глагол to play в нужной форме.
Так как в предложении есть указание на время from two till three yesterday (с двух до трех вчера), используем Past Continuous.
Helen was playing computer games from two till three yesterday.
Ответ: Helen was playing computer games from two till three yesterday.