Question

We all know that we ________ our carbon footprint, but I suspect that many people wouldn't be prepared to go as far as Joan Pick, a retired scientist living in south London.

A．must have reduced	B．should have reduced
C．may have reduced	D．could have reduced

Answer 1

B

B 考察情態(tài)動(dòng)詞。句義：我們都知道本應(yīng)該減少碳，但是我懷疑很少有人能夠項(xiàng)Joan Pick一樣。Must have done表示對(duì)過去情況的肯定推測(cè)。過去一定…；should have done本應(yīng)該做某事，實(shí)際上卻未做。May have done或許…；表示沒有太大的把握，根據(jù)句義說明B正確。