急性坏死性溃疡性龈炎好发于
A.婴幼儿
B.青壮年
C.以上均不正确
D.老年人
E.青少年
参考答案:B
The number of people invited to the party________fifty,but a number of them________absent for
different reasons.[ ]
A.were;was
B.was;was
C.was;were
D.were;were
A.
{$mediaurl}B.
C.
D.
E.
F.