A number of experts ________ invited, but the number of the experts who attended the conference ________ only 20．

1. A.
   were; was
2. B.
   was; were
3. C.
   was; was
4. D.
   were; were

A number of experts ________ invited, but the number of the experts who attended the conference ________ only 20．

[　　]

A. were；was     B. was；were 　　  C. was；was　　 D.  were；were

A number of experts________invited，but the number of the experts who attended the conference_______ only 20.

A. were；was     B. was；were 　　  C. was；was　　 D.  were；were