The car must have been doing at least 100 miles an hour.
这车速肯定每小时至少100英里。
Biological systems have been doing this for billions of years
生物系统亿万年来一直都是这样。
Some scientists have been doing research on artificial internal organs.
一些科学家一直在研究人造内脏。
It is said the industrial production has been doing well.
据说工业生产一直很好。
China has been doing its bit to act the part.
中国一直在尽力的做它应该做的事情。
He has been doing mass work and engaged in scientific research.
他一直从事群众工作和科学科研工作。