化学用语是我们学习化学的工具，它们分别具有各自的意义。下列化学用语只有微观意义的是 [ ]
A．Cu
B．Cl2
C．2N
D．CO2
答案：C
药用部位为成熟果实的是( )
A．砂仁 B．金银花 C．地黄 D．延胡索 E．三七
John received an invitation to a dinner, and with his work____, he gladly accepted it.
A．finished
B．finishing
C．to finish
D．was finished
