问题补充:
I admit that all these problems are difficult, I don’t agree that they cannot be solved.
A. Unless
B. While
C. Until
D. Since
答案:
A. Unless
(答案→)B. While
C. Until
D. Since
解析:考查连词辨析。A除非,如果…不;B当…时;然而;可是;尽管;C直到…才…;D自从,既然;句意:尽管我承认所有的问题都很难,但是我不同意他们都不能被解决。故B正确。