1. He (to play) computer games at five o'clock yesterday.
В задании необходимо употребить глагол to play в нужной форме.
Так как в предложении есть указание на время five o'clock yesterday (в пять часов вчера), используем Past Continuous.
He was playing computer games at five o'clock yesterday.
Ответ: He was playing computer games at five o'clock yesterday.