下列有鉴别意义的细菌代谢产物是()。
A.酸和气体
B.靛基质
C.H2S
D.色素
E.以上均是
参考答案:E
Teenagers are not allowed to stay out late _ school nights.
A.on
B.in
C.at
D.by
All don''t have a free ticket must pay the admission fee.
A.Everyone who doesn't have a free ticket
B.No one who doesn't have a free ticket
C.No one who has free tickets
D.Anyone who has free tickets