The car must have been doing at least 100 miles an hour.

　　這車速肯定每小時(shí)至少100英里。

　　Biological systems have been doing this for billions of years

　　生物系統(tǒng)億萬年來一直都是這樣。

　　Some scientists have been doing research on artificial internal organs.

　　一些科學(xué)家一直在研究人造內(nèi)臟。

　　It is said the industrial production has been doing well.

　　據(jù)說工業(yè)生產(chǎn)一直很好。

　　China has been doing its bit to act the part.

　　中國(guó)一直在盡力的做它應(yīng)該做的事情。

　　He has been doing mass work and engaged in scientific research.

　　他一直從事群眾工作和科學(xué)科研工作。