问题补充：
Nobody but doctors and those by Dr Smith to enter the patient’s room.
A. invited; is allowed
B. invited; are allowed
C. being invited; is allowed
D. being invited; are allowed
答案：
(答案→)A. invited; is allowed
B. invited; are allowed
C. being invited; is allowed
D. being invited; are allowed
解析：考察分词作定语和主谓一致。本题第一空的动词invite与前面的名词those构成被动关系，故使用过去分词短语在句中作定语修饰名词。第二空当A as well as/together with B做主语的时候，要和名词A保持一致。句意：除了医生和那些史密斯博士邀请的人之外没有人被允许进入病人的房间。故A正确。
