After two years’ research we now have a better understanding of the disease.A. veryB. fa

问题补充：

After two years’ research, we now have a better understanding of the disease.

A. very

B. far

C. fairly

D. quite

答案：

A. very

(答案→)B. far

C. fairly

D. quite

解析：副词辨析. A. 非常 B. 很深的程度 C. 相当的D. 相当;完全.句意:在两年的调查之后,现在我们对该病有了更深入的了解.结合语境可知选B.