It was a period of intense activity.
那是活動激烈的'時期。
Economic activity often follows a cyclical pattern.
經濟活動常常遵循周期性模式。
He watched for signs of activity in the house.
他注視著那所房子里的動靜。
The whole place was a scene of feverish activity.
整個地方都是一片緊張匆忙的景象。
He watched the house for signs of activity.
他注視著那所房子里的動靜。