Raindrops fall at a speed of about 500 to 1,000 feet a minute.雨点以每分钟大约五百到一千英尺的速度下降。The train is travelling at a speed of sixty miles an hour.火车正以每小时六十英里的速度行驶。This flight is now proceeding to Paris at a speed of 1 000 kilometres an hour.这次飞行现在正以每小时一千公里的速度向巴黎进发。